import numpy as np
import matplotlib.pyplot as plt
plt.style.use('fivethirtyeight')
plt.rcParams.update({
    "text.usetex": True,
    "font.family": "sans-serif"
})
#plt.rcParams['text.latex.preamble']=[r'sansmath']
from IPython.display import YouTubeVideo
YouTubeVideo('uOq4AbvWF08')

Rolling on hemisphere#

rolling on hemisphere note

In this example, a small ball with negligible moment of inertia rolls on a hemisphere and loses contact at some point. Your goal is to determine the point where the ball loses contact with the hemisphere. The hemisphere has radius, \(R=1~m\), and the ball has mass \(m=1~kg\).

There are two states in this problem:

  1. Ball and hemisphere are in contact with normal force \(N>0\)

  2. Ball and hemisphere are not in contact, so normal force \(N=0\)

There cannot be a state where \(N<0\) because that would mean there is an attractive force between the ball and hemisphere.

Equation of motion and contact force#

Using the free body diagram and kinetic diagram, you can derive these two equations for state 1 (contact):

  1. \(\ddot{\theta} = \frac{g}{R}\sin\theta\)

  2. \(N = mg\cos\theta-mR\dot{\theta}^2\)

Integrate equation 1 by using the chain rule,

\(\frac{d\theta}{d\theta}\frac{d\dot{\theta}}{dt} = \frac{g}{R}\sin\theta\)

\(\frac{d\theta}{dt}\frac{d\dot{\theta}}{d\theta} = \frac{g}{R}\sin\theta\)

\(\int_{\dot{\theta}_0}^{\dot{\theta}}\dot{\theta}d\dot{\theta} = \int_{\theta_0}^{\theta}\frac{2g}{R}\sin\theta\)

\(\dot{\theta} = \sqrt{\dot{\theta}_0^2+\frac{g}{R}(\cos\theta_0-\cos\theta)}\)

Now, you plot the relation between \(\theta\) and \(\dot{\theta}\) for initial conditions,

  • \(\theta_0 = 0~rad\) and \(\dot{\theta}_0=0~rad/s\)

  • \(\theta_0 = 0~rad\) and \(\dot{\theta}_0=2~rad/s\)

  • \(\theta_0 = 0~rad\) and \(\dot{\theta}_0=4~rad/s\)

__Reflection:__When do you expect the ball to lose contact for 0, 2, and 4 rad/s angular velocities? Will it happen sooner or later if the ball is travelling faster at the top of the hemisphere?

theta = np.linspace(0,np.pi)
dtheta = lambda dt0,theta: np.sqrt(dt0**2+2*9.81/1*(1-np.cos(theta)))
plt.plot(theta*180/np.pi, dtheta(0, theta), label=r'$\dot{\theta}_0=0~rad/s$')
plt.plot(theta*180/np.pi, dtheta(2, theta), label=r'$\dot{\theta}_0=2~rad/s$')
plt.plot(theta*180/np.pi, dtheta(4, theta), label=r'$\dot{\theta}_0=4~rad/s$')
plt.title('speed vs angle along hemisphere')
plt.legend()
plt.xlabel(r'$\theta$ (deg)')
plt.ylabel(r'$\dot{\theta}$ (rad/s)');
Error in callback <function _draw_all_if_interactive at 0x7fe274ab1dc0> (for post_execute), with arguments args (),kwargs {}:
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:250, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    249 try:
--> 250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:424, in check_output(timeout, *popenargs, **kwargs)
    422     kwargs['input'] = empty
--> 424 return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
    425            **kwargs).stdout

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:505, in run(input, capture_output, timeout, check, *popenargs, **kwargs)
    503     kwargs['stderr'] = PIPE
--> 505 with Popen(*popenargs, **kwargs) as process:
    506     try:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:951, in Popen.__init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, user, group, extra_groups, encoding, errors, text, umask)
    948             self.stderr = io.TextIOWrapper(self.stderr,
    949                     encoding=encoding, errors=errors)
--> 951     self._execute_child(args, executable, preexec_fn, close_fds,
    952                         pass_fds, cwd, env,
    953                         startupinfo, creationflags, shell,
    954                         p2cread, p2cwrite,
    955                         c2pread, c2pwrite,
    956                         errread, errwrite,
    957                         restore_signals,
    958                         gid, gids, uid, umask,
    959                         start_new_session)
    960 except:
    961     # Cleanup if the child failed starting.

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:1837, in Popen._execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, restore_signals, gid, gids, uid, umask, start_new_session)
   1836         err_msg = os.strerror(errno_num)
-> 1837     raise child_exception_type(errno_num, err_msg, err_filename)
   1838 raise child_exception_type(err_msg)

FileNotFoundError: [Errno 2] No such file or directory: 'latex'

The above exception was the direct cause of the following exception:

RuntimeError                              Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/pyplot.py:197, in _draw_all_if_interactive()
    195 def _draw_all_if_interactive() -> None:
    196     if matplotlib.is_interactive():
--> 197         draw_all()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/_pylab_helpers.py:132, in Gcf.draw_all(cls, force)
    130 for manager in cls.get_all_fig_managers():
    131     if force or manager.canvas.figure.stale:
--> 132         manager.canvas.draw_idle()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:1893, in FigureCanvasBase.draw_idle(self, *args, **kwargs)
   1891 if not self._is_idle_drawing:
   1892     with self._idle_draw_cntx():
-> 1893         self.draw(*args, **kwargs)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:388, in FigureCanvasAgg.draw(self)
    385 # Acquire a lock on the shared font cache.
    386 with (self.toolbar._wait_cursor_for_draw_cm() if self.toolbar
    387       else nullcontext()):
--> 388     self.figure.draw(self.renderer)
    389     # A GUI class may be need to update a window using this draw, so
    390     # don't forget to call the superclass.
    391     super().draw()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:95, in _finalize_rasterization.<locals>.draw_wrapper(artist, renderer, *args, **kwargs)
     93 @wraps(draw)
     94 def draw_wrapper(artist, renderer, *args, **kwargs):
---> 95     result = draw(artist, renderer, *args, **kwargs)
     96     if renderer._rasterizing:
     97         renderer.stop_rasterizing()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/figure.py:3154, in Figure.draw(self, renderer)
   3151         # ValueError can occur when resizing a window.
   3153 self.patch.draw(renderer)
-> 3154 mimage._draw_list_compositing_images(
   3155     renderer, self, artists, self.suppressComposite)
   3157 for sfig in self.subfigs:
   3158     sfig.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:3034, in _AxesBase.draw(self, renderer)
   3031     for spine in self.spines.values():
   3032         artists.remove(spine)
-> 3034 self._update_title_position(renderer)
   3036 if not self.axison:
   3037     for _axis in self._axis_map.values():

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:2978, in _AxesBase._update_title_position(self, renderer)
   2976 top = max(top, bb.ymax)
   2977 if title.get_text():
-> 2978     ax.yaxis.get_tightbbox(renderer)  # update offsetText
   2979     if ax.yaxis.offsetText.get_text():
   2980         bb = ax.yaxis.offsetText.get_tightbbox(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1336, in Axis.get_tightbbox(self, renderer, for_layout_only)
   1333     renderer = self.figure._get_renderer()
   1334 ticks_to_draw = self._update_ticks()
-> 1336 self._update_label_position(renderer)
   1338 # go back to just this axis's tick labels
   1339 tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2609, in YAxis._update_label_position(self, renderer)
   2605     return
   2607 # get bounding boxes for this axis and any siblings
   2608 # that have been set by `fig.align_ylabels()`
-> 2609 bboxes, bboxes2 = self._get_tick_boxes_siblings(renderer=renderer)
   2610 x, y = self.label.get_position()
   2611 if self.label_position == 'left':

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2161, in Axis._get_tick_boxes_siblings(self, renderer)
   2159 axis = ax._axis_map[name]
   2160 ticks_to_draw = axis._update_ticks()
-> 2161 tlb, tlb2 = axis._get_ticklabel_bboxes(ticks_to_draw, renderer)
   2162 bboxes.extend(tlb)
   2163 bboxes2.extend(tlb2)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in Axis._get_ticklabel_bboxes(self, ticks, renderer)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in <listcomp>(.0)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:956, in Text.get_window_extent(self, renderer, dpi)
    951     raise RuntimeError(
    952         "Cannot get window extent of text w/o renderer. You likely "
    953         "want to call 'figure.draw_without_rendering()' first.")
    955 with cbook._setattr_cm(self.figure, dpi=dpi):
--> 956     bbox, info, descent = self._get_layout(self._renderer)
    957     x, y = self.get_unitless_position()
    958     x, y = self.get_transform().transform((x, y))

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:373, in Text._get_layout(self, renderer)
    370 ys = []
    372 # Full vertical extent of font, including ascenders and descenders:
--> 373 _, lp_h, lp_d = _get_text_metrics_with_cache(
    374     renderer, "lp", self._fontproperties,
    375     ismath="TeX" if self.get_usetex() else False, dpi=self.figure.dpi)
    376 min_dy = (lp_h - lp_d) * self._linespacing
    378 for i, line in enumerate(lines):

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:69, in _get_text_metrics_with_cache(renderer, text, fontprop, ismath, dpi)
     66 """Call ``renderer.get_text_width_height_descent``, caching the results."""
     67 # Cached based on a copy of fontprop so that later in-place mutations of
     68 # the passed-in argument do not mess up the cache.
---> 69 return _get_text_metrics_with_cache_impl(
     70     weakref.ref(renderer), text, fontprop.copy(), ismath, dpi)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:77, in _get_text_metrics_with_cache_impl(renderer_ref, text, fontprop, ismath, dpi)
     73 @functools.lru_cache(4096)
     74 def _get_text_metrics_with_cache_impl(
     75         renderer_ref, text, fontprop, ismath, dpi):
     76     # dpi is unused, but participates in cache invalidation (via the renderer).
---> 77     return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:213, in RendererAgg.get_text_width_height_descent(self, s, prop, ismath)
    211 _api.check_in_list(["TeX", True, False], ismath=ismath)
    212 if ismath == "TeX":
--> 213     return super().get_text_width_height_descent(s, prop, ismath)
    215 if ismath:
    216     ox, oy, width, height, descent, font_image = \
    217         self.mathtext_parser.parse(s, self.dpi, prop)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:652, in RendererBase.get_text_width_height_descent(self, s, prop, ismath)
    648 fontsize = prop.get_size_in_points()
    650 if ismath == 'TeX':
    651     # todo: handle properties
--> 652     return self.get_texmanager().get_text_width_height_descent(
    653         s, fontsize, renderer=self)
    655 dpi = self.points_to_pixels(72)
    656 if ismath:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:363, in TexManager.get_text_width_height_descent(cls, tex, fontsize, renderer)
    361 if tex.strip() == '':
    362     return 0, 0, 0
--> 363 dvifile = cls.make_dvi(tex, fontsize)
    364 dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
    365 with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:295, in TexManager.make_dvi(cls, tex, fontsize)
    293     with TemporaryDirectory(dir=cwd) as tmpdir:
    294         tmppath = Path(tmpdir)
--> 295         cls._run_checked_subprocess(
    296             ["latex", "-interaction=nonstopmode", "--halt-on-error",
    297              f"--output-directory={tmppath.name}",
    298              f"{texfile.name}"], tex, cwd=cwd)
    299         (tmppath / Path(dvifile).name).replace(dvifile)
    300 return dvifile

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:254, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:
--> 254     raise RuntimeError(
    255         f'Failed to process string with tex because {command[0]} '
    256         'could not be found') from exc
    257 except subprocess.CalledProcessError as exc:
    258     raise RuntimeError(
    259         '{prog} was not able to process the following string:\n'
    260         '{tex!r}\n\n'
   (...)
    267             exc=exc.output.decode('utf-8', 'backslashreplace'))
    268         ) from None

RuntimeError: Failed to process string with tex because latex could not be found
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:250, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    249 try:
--> 250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:424, in check_output(timeout, *popenargs, **kwargs)
    422     kwargs['input'] = empty
--> 424 return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
    425            **kwargs).stdout

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:505, in run(input, capture_output, timeout, check, *popenargs, **kwargs)
    503     kwargs['stderr'] = PIPE
--> 505 with Popen(*popenargs, **kwargs) as process:
    506     try:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:951, in Popen.__init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, user, group, extra_groups, encoding, errors, text, umask)
    948             self.stderr = io.TextIOWrapper(self.stderr,
    949                     encoding=encoding, errors=errors)
--> 951     self._execute_child(args, executable, preexec_fn, close_fds,
    952                         pass_fds, cwd, env,
    953                         startupinfo, creationflags, shell,
    954                         p2cread, p2cwrite,
    955                         c2pread, c2pwrite,
    956                         errread, errwrite,
    957                         restore_signals,
    958                         gid, gids, uid, umask,
    959                         start_new_session)
    960 except:
    961     # Cleanup if the child failed starting.

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:1837, in Popen._execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, restore_signals, gid, gids, uid, umask, start_new_session)
   1836         err_msg = os.strerror(errno_num)
-> 1837     raise child_exception_type(errno_num, err_msg, err_filename)
   1838 raise child_exception_type(err_msg)

FileNotFoundError: [Errno 2] No such file or directory: 'latex'

The above exception was the direct cause of the following exception:

RuntimeError                              Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/IPython/core/formatters.py:340, in BaseFormatter.__call__(self, obj)
    338     pass
    339 else:
--> 340     return printer(obj)
    341 # Finally look for special method names
    342 method = get_real_method(obj, self.print_method)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/IPython/core/pylabtools.py:152, in print_figure(fig, fmt, bbox_inches, base64, **kwargs)
    149     from matplotlib.backend_bases import FigureCanvasBase
    150     FigureCanvasBase(fig)
--> 152 fig.canvas.print_figure(bytes_io, **kw)
    153 data = bytes_io.getvalue()
    154 if fmt == 'svg':

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:2164, in FigureCanvasBase.print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, bbox_inches, pad_inches, bbox_extra_artists, backend, **kwargs)
   2161     # we do this instead of `self.figure.draw_without_rendering`
   2162     # so that we can inject the orientation
   2163     with getattr(renderer, "_draw_disabled", nullcontext)():
-> 2164         self.figure.draw(renderer)
   2165 if bbox_inches:
   2166     if bbox_inches == "tight":

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:95, in _finalize_rasterization.<locals>.draw_wrapper(artist, renderer, *args, **kwargs)
     93 @wraps(draw)
     94 def draw_wrapper(artist, renderer, *args, **kwargs):
---> 95     result = draw(artist, renderer, *args, **kwargs)
     96     if renderer._rasterizing:
     97         renderer.stop_rasterizing()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/figure.py:3154, in Figure.draw(self, renderer)
   3151         # ValueError can occur when resizing a window.
   3153 self.patch.draw(renderer)
-> 3154 mimage._draw_list_compositing_images(
   3155     renderer, self, artists, self.suppressComposite)
   3157 for sfig in self.subfigs:
   3158     sfig.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:3034, in _AxesBase.draw(self, renderer)
   3031     for spine in self.spines.values():
   3032         artists.remove(spine)
-> 3034 self._update_title_position(renderer)
   3036 if not self.axison:
   3037     for _axis in self._axis_map.values():

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:2978, in _AxesBase._update_title_position(self, renderer)
   2976 top = max(top, bb.ymax)
   2977 if title.get_text():
-> 2978     ax.yaxis.get_tightbbox(renderer)  # update offsetText
   2979     if ax.yaxis.offsetText.get_text():
   2980         bb = ax.yaxis.offsetText.get_tightbbox(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1336, in Axis.get_tightbbox(self, renderer, for_layout_only)
   1333     renderer = self.figure._get_renderer()
   1334 ticks_to_draw = self._update_ticks()
-> 1336 self._update_label_position(renderer)
   1338 # go back to just this axis's tick labels
   1339 tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2609, in YAxis._update_label_position(self, renderer)
   2605     return
   2607 # get bounding boxes for this axis and any siblings
   2608 # that have been set by `fig.align_ylabels()`
-> 2609 bboxes, bboxes2 = self._get_tick_boxes_siblings(renderer=renderer)
   2610 x, y = self.label.get_position()
   2611 if self.label_position == 'left':

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2161, in Axis._get_tick_boxes_siblings(self, renderer)
   2159 axis = ax._axis_map[name]
   2160 ticks_to_draw = axis._update_ticks()
-> 2161 tlb, tlb2 = axis._get_ticklabel_bboxes(ticks_to_draw, renderer)
   2162 bboxes.extend(tlb)
   2163 bboxes2.extend(tlb2)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in Axis._get_ticklabel_bboxes(self, ticks, renderer)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in <listcomp>(.0)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:956, in Text.get_window_extent(self, renderer, dpi)
    951     raise RuntimeError(
    952         "Cannot get window extent of text w/o renderer. You likely "
    953         "want to call 'figure.draw_without_rendering()' first.")
    955 with cbook._setattr_cm(self.figure, dpi=dpi):
--> 956     bbox, info, descent = self._get_layout(self._renderer)
    957     x, y = self.get_unitless_position()
    958     x, y = self.get_transform().transform((x, y))

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:373, in Text._get_layout(self, renderer)
    370 ys = []
    372 # Full vertical extent of font, including ascenders and descenders:
--> 373 _, lp_h, lp_d = _get_text_metrics_with_cache(
    374     renderer, "lp", self._fontproperties,
    375     ismath="TeX" if self.get_usetex() else False, dpi=self.figure.dpi)
    376 min_dy = (lp_h - lp_d) * self._linespacing
    378 for i, line in enumerate(lines):

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:69, in _get_text_metrics_with_cache(renderer, text, fontprop, ismath, dpi)
     66 """Call ``renderer.get_text_width_height_descent``, caching the results."""
     67 # Cached based on a copy of fontprop so that later in-place mutations of
     68 # the passed-in argument do not mess up the cache.
---> 69 return _get_text_metrics_with_cache_impl(
     70     weakref.ref(renderer), text, fontprop.copy(), ismath, dpi)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:77, in _get_text_metrics_with_cache_impl(renderer_ref, text, fontprop, ismath, dpi)
     73 @functools.lru_cache(4096)
     74 def _get_text_metrics_with_cache_impl(
     75         renderer_ref, text, fontprop, ismath, dpi):
     76     # dpi is unused, but participates in cache invalidation (via the renderer).
---> 77     return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:213, in RendererAgg.get_text_width_height_descent(self, s, prop, ismath)
    211 _api.check_in_list(["TeX", True, False], ismath=ismath)
    212 if ismath == "TeX":
--> 213     return super().get_text_width_height_descent(s, prop, ismath)
    215 if ismath:
    216     ox, oy, width, height, descent, font_image = \
    217         self.mathtext_parser.parse(s, self.dpi, prop)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:652, in RendererBase.get_text_width_height_descent(self, s, prop, ismath)
    648 fontsize = prop.get_size_in_points()
    650 if ismath == 'TeX':
    651     # todo: handle properties
--> 652     return self.get_texmanager().get_text_width_height_descent(
    653         s, fontsize, renderer=self)
    655 dpi = self.points_to_pixels(72)
    656 if ismath:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:363, in TexManager.get_text_width_height_descent(cls, tex, fontsize, renderer)
    361 if tex.strip() == '':
    362     return 0, 0, 0
--> 363 dvifile = cls.make_dvi(tex, fontsize)
    364 dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
    365 with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:295, in TexManager.make_dvi(cls, tex, fontsize)
    293     with TemporaryDirectory(dir=cwd) as tmpdir:
    294         tmppath = Path(tmpdir)
--> 295         cls._run_checked_subprocess(
    296             ["latex", "-interaction=nonstopmode", "--halt-on-error",
    297              f"--output-directory={tmppath.name}",
    298              f"{texfile.name}"], tex, cwd=cwd)
    299         (tmppath / Path(dvifile).name).replace(dvifile)
    300 return dvifile

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:254, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:
--> 254     raise RuntimeError(
    255         f'Failed to process string with tex because {command[0]} '
    256         'could not be found') from exc
    257 except subprocess.CalledProcessError as exc:
    258     raise RuntimeError(
    259         '{prog} was not able to process the following string:\n'
    260         '{tex!r}\n\n'
   (...)
    267             exc=exc.output.decode('utf-8', 'backslashreplace'))
    268         ) from None

RuntimeError: Failed to process string with tex because latex could not be found
<Figure size 640x480 with 1 Axes>

Normal force prediction#

The second equation relates the normal force, \(N\) to \(\theta\) and \(\dot{\theta}\). Now, plot the \(N-vs-\theta\).

\(N = mg\cos\theta-mR\dot{\theta}^2\)

If this equation predicts \(N<0\), then the ball has lost contact with the hemisphere. It will transition into a freefalling object with initial position and velocity,

When N=0, transition state:

  • \(\mathbf{r} = R\hat{e}_r=R(\sin\theta\hat{i}+\cos\theta\hat{j})\)

  • \(\mathbf{v} = R\dot{\theta}\hat{e}_{\theta}= R\dot{\theta}(\cos\theta\hat{i}-\sin\theta\hat{j})\)

Below, you see the plots for \(N-vs-\theta\) for \(\theta = 0-180^o\),

N0 = 9.81*np.cos(theta)-1*dtheta(0, theta)**2
N2 = 9.81*np.cos(theta)-1*dtheta(2, theta)**2
N4 = 9.81*np.cos(theta)-1*dtheta(4, theta)**2

plt.plot(theta*180/np.pi, N0, label=r'$\dot{\theta}_0=0~rad/s$')
plt.plot(theta*180/np.pi, N2, label=r'$\dot{\theta}_0=2~rad/s$')
plt.plot(theta*180/np.pi, N4, label=r'$\dot{\theta}_0=4~rad/s$')
plt.xlabel(r'$\theta$ (deg)')
plt.ylabel(r'N (N)')
plt.legend()
<matplotlib.legend.Legend at 0x7fe271321be0>
Error in callback <function _draw_all_if_interactive at 0x7fe274ab1dc0> (for post_execute), with arguments args (),kwargs {}:
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:250, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    249 try:
--> 250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:424, in check_output(timeout, *popenargs, **kwargs)
    422     kwargs['input'] = empty
--> 424 return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
    425            **kwargs).stdout

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:505, in run(input, capture_output, timeout, check, *popenargs, **kwargs)
    503     kwargs['stderr'] = PIPE
--> 505 with Popen(*popenargs, **kwargs) as process:
    506     try:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:951, in Popen.__init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, user, group, extra_groups, encoding, errors, text, umask)
    948             self.stderr = io.TextIOWrapper(self.stderr,
    949                     encoding=encoding, errors=errors)
--> 951     self._execute_child(args, executable, preexec_fn, close_fds,
    952                         pass_fds, cwd, env,
    953                         startupinfo, creationflags, shell,
    954                         p2cread, p2cwrite,
    955                         c2pread, c2pwrite,
    956                         errread, errwrite,
    957                         restore_signals,
    958                         gid, gids, uid, umask,
    959                         start_new_session)
    960 except:
    961     # Cleanup if the child failed starting.

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:1837, in Popen._execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, restore_signals, gid, gids, uid, umask, start_new_session)
   1836         err_msg = os.strerror(errno_num)
-> 1837     raise child_exception_type(errno_num, err_msg, err_filename)
   1838 raise child_exception_type(err_msg)

FileNotFoundError: [Errno 2] No such file or directory: 'latex'

The above exception was the direct cause of the following exception:

RuntimeError                              Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/pyplot.py:197, in _draw_all_if_interactive()
    195 def _draw_all_if_interactive() -> None:
    196     if matplotlib.is_interactive():
--> 197         draw_all()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/_pylab_helpers.py:132, in Gcf.draw_all(cls, force)
    130 for manager in cls.get_all_fig_managers():
    131     if force or manager.canvas.figure.stale:
--> 132         manager.canvas.draw_idle()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:1893, in FigureCanvasBase.draw_idle(self, *args, **kwargs)
   1891 if not self._is_idle_drawing:
   1892     with self._idle_draw_cntx():
-> 1893         self.draw(*args, **kwargs)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:388, in FigureCanvasAgg.draw(self)
    385 # Acquire a lock on the shared font cache.
    386 with (self.toolbar._wait_cursor_for_draw_cm() if self.toolbar
    387       else nullcontext()):
--> 388     self.figure.draw(self.renderer)
    389     # A GUI class may be need to update a window using this draw, so
    390     # don't forget to call the superclass.
    391     super().draw()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:95, in _finalize_rasterization.<locals>.draw_wrapper(artist, renderer, *args, **kwargs)
     93 @wraps(draw)
     94 def draw_wrapper(artist, renderer, *args, **kwargs):
---> 95     result = draw(artist, renderer, *args, **kwargs)
     96     if renderer._rasterizing:
     97         renderer.stop_rasterizing()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/figure.py:3154, in Figure.draw(self, renderer)
   3151         # ValueError can occur when resizing a window.
   3153 self.patch.draw(renderer)
-> 3154 mimage._draw_list_compositing_images(
   3155     renderer, self, artists, self.suppressComposite)
   3157 for sfig in self.subfigs:
   3158     sfig.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:3070, in _AxesBase.draw(self, renderer)
   3067 if artists_rasterized:
   3068     _draw_rasterized(self.figure, artists_rasterized, renderer)
-> 3070 mimage._draw_list_compositing_images(
   3071     renderer, self, artists, self.figure.suppressComposite)
   3073 renderer.close_group('axes')
   3074 self.stale = False

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1388, in Axis.draw(self, renderer, *args, **kwargs)
   1385 renderer.open_group(__name__, gid=self.get_gid())
   1387 ticks_to_draw = self._update_ticks()
-> 1388 tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer)
   1390 for tick in ticks_to_draw:
   1391     tick.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in Axis._get_ticklabel_bboxes(self, ticks, renderer)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in <listcomp>(.0)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:956, in Text.get_window_extent(self, renderer, dpi)
    951     raise RuntimeError(
    952         "Cannot get window extent of text w/o renderer. You likely "
    953         "want to call 'figure.draw_without_rendering()' first.")
    955 with cbook._setattr_cm(self.figure, dpi=dpi):
--> 956     bbox, info, descent = self._get_layout(self._renderer)
    957     x, y = self.get_unitless_position()
    958     x, y = self.get_transform().transform((x, y))

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:373, in Text._get_layout(self, renderer)
    370 ys = []
    372 # Full vertical extent of font, including ascenders and descenders:
--> 373 _, lp_h, lp_d = _get_text_metrics_with_cache(
    374     renderer, "lp", self._fontproperties,
    375     ismath="TeX" if self.get_usetex() else False, dpi=self.figure.dpi)
    376 min_dy = (lp_h - lp_d) * self._linespacing
    378 for i, line in enumerate(lines):

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:69, in _get_text_metrics_with_cache(renderer, text, fontprop, ismath, dpi)
     66 """Call ``renderer.get_text_width_height_descent``, caching the results."""
     67 # Cached based on a copy of fontprop so that later in-place mutations of
     68 # the passed-in argument do not mess up the cache.
---> 69 return _get_text_metrics_with_cache_impl(
     70     weakref.ref(renderer), text, fontprop.copy(), ismath, dpi)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:77, in _get_text_metrics_with_cache_impl(renderer_ref, text, fontprop, ismath, dpi)
     73 @functools.lru_cache(4096)
     74 def _get_text_metrics_with_cache_impl(
     75         renderer_ref, text, fontprop, ismath, dpi):
     76     # dpi is unused, but participates in cache invalidation (via the renderer).
---> 77     return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:213, in RendererAgg.get_text_width_height_descent(self, s, prop, ismath)
    211 _api.check_in_list(["TeX", True, False], ismath=ismath)
    212 if ismath == "TeX":
--> 213     return super().get_text_width_height_descent(s, prop, ismath)
    215 if ismath:
    216     ox, oy, width, height, descent, font_image = \
    217         self.mathtext_parser.parse(s, self.dpi, prop)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:652, in RendererBase.get_text_width_height_descent(self, s, prop, ismath)
    648 fontsize = prop.get_size_in_points()
    650 if ismath == 'TeX':
    651     # todo: handle properties
--> 652     return self.get_texmanager().get_text_width_height_descent(
    653         s, fontsize, renderer=self)
    655 dpi = self.points_to_pixels(72)
    656 if ismath:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:363, in TexManager.get_text_width_height_descent(cls, tex, fontsize, renderer)
    361 if tex.strip() == '':
    362     return 0, 0, 0
--> 363 dvifile = cls.make_dvi(tex, fontsize)
    364 dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
    365 with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:295, in TexManager.make_dvi(cls, tex, fontsize)
    293     with TemporaryDirectory(dir=cwd) as tmpdir:
    294         tmppath = Path(tmpdir)
--> 295         cls._run_checked_subprocess(
    296             ["latex", "-interaction=nonstopmode", "--halt-on-error",
    297              f"--output-directory={tmppath.name}",
    298              f"{texfile.name}"], tex, cwd=cwd)
    299         (tmppath / Path(dvifile).name).replace(dvifile)
    300 return dvifile

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:254, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:
--> 254     raise RuntimeError(
    255         f'Failed to process string with tex because {command[0]} '
    256         'could not be found') from exc
    257 except subprocess.CalledProcessError as exc:
    258     raise RuntimeError(
    259         '{prog} was not able to process the following string:\n'
    260         '{tex!r}\n\n'
   (...)
    267             exc=exc.output.decode('utf-8', 'backslashreplace'))
    268         ) from None

RuntimeError: Failed to process string with tex because latex could not be found
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:250, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    249 try:
--> 250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:424, in check_output(timeout, *popenargs, **kwargs)
    422     kwargs['input'] = empty
--> 424 return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
    425            **kwargs).stdout

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:505, in run(input, capture_output, timeout, check, *popenargs, **kwargs)
    503     kwargs['stderr'] = PIPE
--> 505 with Popen(*popenargs, **kwargs) as process:
    506     try:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:951, in Popen.__init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, user, group, extra_groups, encoding, errors, text, umask)
    948             self.stderr = io.TextIOWrapper(self.stderr,
    949                     encoding=encoding, errors=errors)
--> 951     self._execute_child(args, executable, preexec_fn, close_fds,
    952                         pass_fds, cwd, env,
    953                         startupinfo, creationflags, shell,
    954                         p2cread, p2cwrite,
    955                         c2pread, c2pwrite,
    956                         errread, errwrite,
    957                         restore_signals,
    958                         gid, gids, uid, umask,
    959                         start_new_session)
    960 except:
    961     # Cleanup if the child failed starting.

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:1837, in Popen._execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, restore_signals, gid, gids, uid, umask, start_new_session)
   1836         err_msg = os.strerror(errno_num)
-> 1837     raise child_exception_type(errno_num, err_msg, err_filename)
   1838 raise child_exception_type(err_msg)

FileNotFoundError: [Errno 2] No such file or directory: 'latex'

The above exception was the direct cause of the following exception:

RuntimeError                              Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/IPython/core/formatters.py:340, in BaseFormatter.__call__(self, obj)
    338     pass
    339 else:
--> 340     return printer(obj)
    341 # Finally look for special method names
    342 method = get_real_method(obj, self.print_method)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/IPython/core/pylabtools.py:152, in print_figure(fig, fmt, bbox_inches, base64, **kwargs)
    149     from matplotlib.backend_bases import FigureCanvasBase
    150     FigureCanvasBase(fig)
--> 152 fig.canvas.print_figure(bytes_io, **kw)
    153 data = bytes_io.getvalue()
    154 if fmt == 'svg':

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:2164, in FigureCanvasBase.print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, bbox_inches, pad_inches, bbox_extra_artists, backend, **kwargs)
   2161     # we do this instead of `self.figure.draw_without_rendering`
   2162     # so that we can inject the orientation
   2163     with getattr(renderer, "_draw_disabled", nullcontext)():
-> 2164         self.figure.draw(renderer)
   2165 if bbox_inches:
   2166     if bbox_inches == "tight":

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:95, in _finalize_rasterization.<locals>.draw_wrapper(artist, renderer, *args, **kwargs)
     93 @wraps(draw)
     94 def draw_wrapper(artist, renderer, *args, **kwargs):
---> 95     result = draw(artist, renderer, *args, **kwargs)
     96     if renderer._rasterizing:
     97         renderer.stop_rasterizing()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/figure.py:3154, in Figure.draw(self, renderer)
   3151         # ValueError can occur when resizing a window.
   3153 self.patch.draw(renderer)
-> 3154 mimage._draw_list_compositing_images(
   3155     renderer, self, artists, self.suppressComposite)
   3157 for sfig in self.subfigs:
   3158     sfig.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:3070, in _AxesBase.draw(self, renderer)
   3067 if artists_rasterized:
   3068     _draw_rasterized(self.figure, artists_rasterized, renderer)
-> 3070 mimage._draw_list_compositing_images(
   3071     renderer, self, artists, self.figure.suppressComposite)
   3073 renderer.close_group('axes')
   3074 self.stale = False

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1388, in Axis.draw(self, renderer, *args, **kwargs)
   1385 renderer.open_group(__name__, gid=self.get_gid())
   1387 ticks_to_draw = self._update_ticks()
-> 1388 tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer)
   1390 for tick in ticks_to_draw:
   1391     tick.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in Axis._get_ticklabel_bboxes(self, ticks, renderer)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in <listcomp>(.0)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:956, in Text.get_window_extent(self, renderer, dpi)
    951     raise RuntimeError(
    952         "Cannot get window extent of text w/o renderer. You likely "
    953         "want to call 'figure.draw_without_rendering()' first.")
    955 with cbook._setattr_cm(self.figure, dpi=dpi):
--> 956     bbox, info, descent = self._get_layout(self._renderer)
    957     x, y = self.get_unitless_position()
    958     x, y = self.get_transform().transform((x, y))

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:373, in Text._get_layout(self, renderer)
    370 ys = []
    372 # Full vertical extent of font, including ascenders and descenders:
--> 373 _, lp_h, lp_d = _get_text_metrics_with_cache(
    374     renderer, "lp", self._fontproperties,
    375     ismath="TeX" if self.get_usetex() else False, dpi=self.figure.dpi)
    376 min_dy = (lp_h - lp_d) * self._linespacing
    378 for i, line in enumerate(lines):

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:69, in _get_text_metrics_with_cache(renderer, text, fontprop, ismath, dpi)
     66 """Call ``renderer.get_text_width_height_descent``, caching the results."""
     67 # Cached based on a copy of fontprop so that later in-place mutations of
     68 # the passed-in argument do not mess up the cache.
---> 69 return _get_text_metrics_with_cache_impl(
     70     weakref.ref(renderer), text, fontprop.copy(), ismath, dpi)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:77, in _get_text_metrics_with_cache_impl(renderer_ref, text, fontprop, ismath, dpi)
     73 @functools.lru_cache(4096)
     74 def _get_text_metrics_with_cache_impl(
     75         renderer_ref, text, fontprop, ismath, dpi):
     76     # dpi is unused, but participates in cache invalidation (via the renderer).
---> 77     return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:213, in RendererAgg.get_text_width_height_descent(self, s, prop, ismath)
    211 _api.check_in_list(["TeX", True, False], ismath=ismath)
    212 if ismath == "TeX":
--> 213     return super().get_text_width_height_descent(s, prop, ismath)
    215 if ismath:
    216     ox, oy, width, height, descent, font_image = \
    217         self.mathtext_parser.parse(s, self.dpi, prop)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:652, in RendererBase.get_text_width_height_descent(self, s, prop, ismath)
    648 fontsize = prop.get_size_in_points()
    650 if ismath == 'TeX':
    651     # todo: handle properties
--> 652     return self.get_texmanager().get_text_width_height_descent(
    653         s, fontsize, renderer=self)
    655 dpi = self.points_to_pixels(72)
    656 if ismath:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:363, in TexManager.get_text_width_height_descent(cls, tex, fontsize, renderer)
    361 if tex.strip() == '':
    362     return 0, 0, 0
--> 363 dvifile = cls.make_dvi(tex, fontsize)
    364 dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
    365 with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:295, in TexManager.make_dvi(cls, tex, fontsize)
    293     with TemporaryDirectory(dir=cwd) as tmpdir:
    294         tmppath = Path(tmpdir)
--> 295         cls._run_checked_subprocess(
    296             ["latex", "-interaction=nonstopmode", "--halt-on-error",
    297              f"--output-directory={tmppath.name}",
    298              f"{texfile.name}"], tex, cwd=cwd)
    299         (tmppath / Path(dvifile).name).replace(dvifile)
    300 return dvifile

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:254, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:
--> 254     raise RuntimeError(
    255         f'Failed to process string with tex because {command[0]} '
    256         'could not be found') from exc
    257 except subprocess.CalledProcessError as exc:
    258     raise RuntimeError(
    259         '{prog} was not able to process the following string:\n'
    260         '{tex!r}\n\n'
   (...)
    267             exc=exc.output.decode('utf-8', 'backslashreplace'))
    268         ) from None

RuntimeError: Failed to process string with tex because latex could not be found
<Figure size 640x480 with 1 Axes>

Solving for loss-of-contact#

The graph above reveals that at \(\dot{\theta}_0=4~rad/s\), the ball never makes contact with the hemisphere. It skims the top, and falls as

  • \(x(t) = 4t~[m]\)

  • \(y(t) = 1-\frac{g}{2}t^2~[m]\)

In the cases of \(\dot{\theta}_0=0~and~2~rad/s\), the ball loses contact between \(\theta=25^o-50^o\). You can use algebra to solve for \(N(\theta^*)=0\), where \(\theta^*\) is the location where contact is lost.

or

You have Python here that can solve nolinear problems. Import fsolve from the scipy.optimize library.

from scipy.optimize import fsolve

Defining and solving a nonlinear equation#

You have two equations,

  1. \(\dot{\theta} = \sqrt{\dot{\theta}_0^2+\frac{g}{R}(\cos\theta_0-\cos\theta)} = g(\dot{\theta}_0,~\theta)\)

  2. \(N = mg\cos\theta-mR\dot{\theta}^2 = f(\theta,~\dot{\theta}) = f(\theta, g(\dot{\theta}_0,~\theta))\)

For clarity, you can define equation (1) first, then use it in equation (2) as such

dtheta = lambda dt0,theta: np.sqrt(dt0**2+2*9.81/1*(1-np.cos(theta)))
N = lambda dt0, theta: 9.81*np.cos(theta)-1*dtheta(dt0, theta)**2
thetastar_0 = fsolve(lambda x: N(0, x), np.pi/3)*180/np.pi
thetastar_2 = fsolve(lambda x: N(2, x), np.pi/3)*180/np.pi
plt.plot(theta*180/np.pi, N0, label=r'$\dot{\theta}_0=0~rad/s$')
plt.plot(theta*180/np.pi, N2, label=r'$\dot{\theta}_0=2~rad/s$')
plt.plot(theta*180/np.pi, N4, label=r'$\dot{\theta}_0=4~rad/s$')
plt.plot(thetastar_0[0], N(0,thetastar_0*np.pi/180), 'b*', markersize=20)
plt.plot(thetastar_2[0], N(2,thetastar_2*np.pi/180), 'r*', markersize=20)
plt.xlabel(r'$\theta$ (deg)')
plt.ylabel(r'N (N)')
plt.title(r'Lose contact at $\theta=$ '+'{:.2f} and {:.2f}'.format(thetastar_0[0], thetastar_2[0]))
plt.ylim(-20,11)
plt.legend()
<matplotlib.legend.Legend at 0x7fe2673fdcd0>
Error in callback <function _draw_all_if_interactive at 0x7fe274ab1dc0> (for post_execute), with arguments args (),kwargs {}:
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:250, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    249 try:
--> 250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:424, in check_output(timeout, *popenargs, **kwargs)
    422     kwargs['input'] = empty
--> 424 return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
    425            **kwargs).stdout

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:505, in run(input, capture_output, timeout, check, *popenargs, **kwargs)
    503     kwargs['stderr'] = PIPE
--> 505 with Popen(*popenargs, **kwargs) as process:
    506     try:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:951, in Popen.__init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, user, group, extra_groups, encoding, errors, text, umask)
    948             self.stderr = io.TextIOWrapper(self.stderr,
    949                     encoding=encoding, errors=errors)
--> 951     self._execute_child(args, executable, preexec_fn, close_fds,
    952                         pass_fds, cwd, env,
    953                         startupinfo, creationflags, shell,
    954                         p2cread, p2cwrite,
    955                         c2pread, c2pwrite,
    956                         errread, errwrite,
    957                         restore_signals,
    958                         gid, gids, uid, umask,
    959                         start_new_session)
    960 except:
    961     # Cleanup if the child failed starting.

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:1837, in Popen._execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, restore_signals, gid, gids, uid, umask, start_new_session)
   1836         err_msg = os.strerror(errno_num)
-> 1837     raise child_exception_type(errno_num, err_msg, err_filename)
   1838 raise child_exception_type(err_msg)

FileNotFoundError: [Errno 2] No such file or directory: 'latex'

The above exception was the direct cause of the following exception:

RuntimeError                              Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/pyplot.py:197, in _draw_all_if_interactive()
    195 def _draw_all_if_interactive() -> None:
    196     if matplotlib.is_interactive():
--> 197         draw_all()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/_pylab_helpers.py:132, in Gcf.draw_all(cls, force)
    130 for manager in cls.get_all_fig_managers():
    131     if force or manager.canvas.figure.stale:
--> 132         manager.canvas.draw_idle()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:1893, in FigureCanvasBase.draw_idle(self, *args, **kwargs)
   1891 if not self._is_idle_drawing:
   1892     with self._idle_draw_cntx():
-> 1893         self.draw(*args, **kwargs)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:388, in FigureCanvasAgg.draw(self)
    385 # Acquire a lock on the shared font cache.
    386 with (self.toolbar._wait_cursor_for_draw_cm() if self.toolbar
    387       else nullcontext()):
--> 388     self.figure.draw(self.renderer)
    389     # A GUI class may be need to update a window using this draw, so
    390     # don't forget to call the superclass.
    391     super().draw()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:95, in _finalize_rasterization.<locals>.draw_wrapper(artist, renderer, *args, **kwargs)
     93 @wraps(draw)
     94 def draw_wrapper(artist, renderer, *args, **kwargs):
---> 95     result = draw(artist, renderer, *args, **kwargs)
     96     if renderer._rasterizing:
     97         renderer.stop_rasterizing()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/figure.py:3154, in Figure.draw(self, renderer)
   3151         # ValueError can occur when resizing a window.
   3153 self.patch.draw(renderer)
-> 3154 mimage._draw_list_compositing_images(
   3155     renderer, self, artists, self.suppressComposite)
   3157 for sfig in self.subfigs:
   3158     sfig.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:3034, in _AxesBase.draw(self, renderer)
   3031     for spine in self.spines.values():
   3032         artists.remove(spine)
-> 3034 self._update_title_position(renderer)
   3036 if not self.axison:
   3037     for _axis in self._axis_map.values():

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:2978, in _AxesBase._update_title_position(self, renderer)
   2976 top = max(top, bb.ymax)
   2977 if title.get_text():
-> 2978     ax.yaxis.get_tightbbox(renderer)  # update offsetText
   2979     if ax.yaxis.offsetText.get_text():
   2980         bb = ax.yaxis.offsetText.get_tightbbox(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1336, in Axis.get_tightbbox(self, renderer, for_layout_only)
   1333     renderer = self.figure._get_renderer()
   1334 ticks_to_draw = self._update_ticks()
-> 1336 self._update_label_position(renderer)
   1338 # go back to just this axis's tick labels
   1339 tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2609, in YAxis._update_label_position(self, renderer)
   2605     return
   2607 # get bounding boxes for this axis and any siblings
   2608 # that have been set by `fig.align_ylabels()`
-> 2609 bboxes, bboxes2 = self._get_tick_boxes_siblings(renderer=renderer)
   2610 x, y = self.label.get_position()
   2611 if self.label_position == 'left':

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2161, in Axis._get_tick_boxes_siblings(self, renderer)
   2159 axis = ax._axis_map[name]
   2160 ticks_to_draw = axis._update_ticks()
-> 2161 tlb, tlb2 = axis._get_ticklabel_bboxes(ticks_to_draw, renderer)
   2162 bboxes.extend(tlb)
   2163 bboxes2.extend(tlb2)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in Axis._get_ticklabel_bboxes(self, ticks, renderer)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in <listcomp>(.0)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:956, in Text.get_window_extent(self, renderer, dpi)
    951     raise RuntimeError(
    952         "Cannot get window extent of text w/o renderer. You likely "
    953         "want to call 'figure.draw_without_rendering()' first.")
    955 with cbook._setattr_cm(self.figure, dpi=dpi):
--> 956     bbox, info, descent = self._get_layout(self._renderer)
    957     x, y = self.get_unitless_position()
    958     x, y = self.get_transform().transform((x, y))

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:373, in Text._get_layout(self, renderer)
    370 ys = []
    372 # Full vertical extent of font, including ascenders and descenders:
--> 373 _, lp_h, lp_d = _get_text_metrics_with_cache(
    374     renderer, "lp", self._fontproperties,
    375     ismath="TeX" if self.get_usetex() else False, dpi=self.figure.dpi)
    376 min_dy = (lp_h - lp_d) * self._linespacing
    378 for i, line in enumerate(lines):

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:69, in _get_text_metrics_with_cache(renderer, text, fontprop, ismath, dpi)
     66 """Call ``renderer.get_text_width_height_descent``, caching the results."""
     67 # Cached based on a copy of fontprop so that later in-place mutations of
     68 # the passed-in argument do not mess up the cache.
---> 69 return _get_text_metrics_with_cache_impl(
     70     weakref.ref(renderer), text, fontprop.copy(), ismath, dpi)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:77, in _get_text_metrics_with_cache_impl(renderer_ref, text, fontprop, ismath, dpi)
     73 @functools.lru_cache(4096)
     74 def _get_text_metrics_with_cache_impl(
     75         renderer_ref, text, fontprop, ismath, dpi):
     76     # dpi is unused, but participates in cache invalidation (via the renderer).
---> 77     return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:213, in RendererAgg.get_text_width_height_descent(self, s, prop, ismath)
    211 _api.check_in_list(["TeX", True, False], ismath=ismath)
    212 if ismath == "TeX":
--> 213     return super().get_text_width_height_descent(s, prop, ismath)
    215 if ismath:
    216     ox, oy, width, height, descent, font_image = \
    217         self.mathtext_parser.parse(s, self.dpi, prop)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:652, in RendererBase.get_text_width_height_descent(self, s, prop, ismath)
    648 fontsize = prop.get_size_in_points()
    650 if ismath == 'TeX':
    651     # todo: handle properties
--> 652     return self.get_texmanager().get_text_width_height_descent(
    653         s, fontsize, renderer=self)
    655 dpi = self.points_to_pixels(72)
    656 if ismath:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:363, in TexManager.get_text_width_height_descent(cls, tex, fontsize, renderer)
    361 if tex.strip() == '':
    362     return 0, 0, 0
--> 363 dvifile = cls.make_dvi(tex, fontsize)
    364 dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
    365 with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:295, in TexManager.make_dvi(cls, tex, fontsize)
    293     with TemporaryDirectory(dir=cwd) as tmpdir:
    294         tmppath = Path(tmpdir)
--> 295         cls._run_checked_subprocess(
    296             ["latex", "-interaction=nonstopmode", "--halt-on-error",
    297              f"--output-directory={tmppath.name}",
    298              f"{texfile.name}"], tex, cwd=cwd)
    299         (tmppath / Path(dvifile).name).replace(dvifile)
    300 return dvifile

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:254, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:
--> 254     raise RuntimeError(
    255         f'Failed to process string with tex because {command[0]} '
    256         'could not be found') from exc
    257 except subprocess.CalledProcessError as exc:
    258     raise RuntimeError(
    259         '{prog} was not able to process the following string:\n'
    260         '{tex!r}\n\n'
   (...)
    267             exc=exc.output.decode('utf-8', 'backslashreplace'))
    268         ) from None

RuntimeError: Failed to process string with tex because latex could not be found
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:250, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    249 try:
--> 250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:424, in check_output(timeout, *popenargs, **kwargs)
    422     kwargs['input'] = empty
--> 424 return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
    425            **kwargs).stdout

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:505, in run(input, capture_output, timeout, check, *popenargs, **kwargs)
    503     kwargs['stderr'] = PIPE
--> 505 with Popen(*popenargs, **kwargs) as process:
    506     try:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:951, in Popen.__init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, user, group, extra_groups, encoding, errors, text, umask)
    948             self.stderr = io.TextIOWrapper(self.stderr,
    949                     encoding=encoding, errors=errors)
--> 951     self._execute_child(args, executable, preexec_fn, close_fds,
    952                         pass_fds, cwd, env,
    953                         startupinfo, creationflags, shell,
    954                         p2cread, p2cwrite,
    955                         c2pread, c2pwrite,
    956                         errread, errwrite,
    957                         restore_signals,
    958                         gid, gids, uid, umask,
    959                         start_new_session)
    960 except:
    961     # Cleanup if the child failed starting.

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/subprocess.py:1837, in Popen._execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, restore_signals, gid, gids, uid, umask, start_new_session)
   1836         err_msg = os.strerror(errno_num)
-> 1837     raise child_exception_type(errno_num, err_msg, err_filename)
   1838 raise child_exception_type(err_msg)

FileNotFoundError: [Errno 2] No such file or directory: 'latex'

The above exception was the direct cause of the following exception:

RuntimeError                              Traceback (most recent call last)
File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/IPython/core/formatters.py:340, in BaseFormatter.__call__(self, obj)
    338     pass
    339 else:
--> 340     return printer(obj)
    341 # Finally look for special method names
    342 method = get_real_method(obj, self.print_method)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/IPython/core/pylabtools.py:152, in print_figure(fig, fmt, bbox_inches, base64, **kwargs)
    149     from matplotlib.backend_bases import FigureCanvasBase
    150     FigureCanvasBase(fig)
--> 152 fig.canvas.print_figure(bytes_io, **kw)
    153 data = bytes_io.getvalue()
    154 if fmt == 'svg':

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:2164, in FigureCanvasBase.print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, bbox_inches, pad_inches, bbox_extra_artists, backend, **kwargs)
   2161     # we do this instead of `self.figure.draw_without_rendering`
   2162     # so that we can inject the orientation
   2163     with getattr(renderer, "_draw_disabled", nullcontext)():
-> 2164         self.figure.draw(renderer)
   2165 if bbox_inches:
   2166     if bbox_inches == "tight":

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:95, in _finalize_rasterization.<locals>.draw_wrapper(artist, renderer, *args, **kwargs)
     93 @wraps(draw)
     94 def draw_wrapper(artist, renderer, *args, **kwargs):
---> 95     result = draw(artist, renderer, *args, **kwargs)
     96     if renderer._rasterizing:
     97         renderer.stop_rasterizing()

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/figure.py:3154, in Figure.draw(self, renderer)
   3151         # ValueError can occur when resizing a window.
   3153 self.patch.draw(renderer)
-> 3154 mimage._draw_list_compositing_images(
   3155     renderer, self, artists, self.suppressComposite)
   3157 for sfig in self.subfigs:
   3158     sfig.draw(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/image.py:132, in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    130 if not_composite or not has_images:
    131     for a in artists:
--> 132         a.draw(renderer)
    133 else:
    134     # Composite any adjacent images together
    135     image_group = []

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/artist.py:72, in allow_rasterization.<locals>.draw_wrapper(artist, renderer)
     69     if artist.get_agg_filter() is not None:
     70         renderer.start_filter()
---> 72     return draw(artist, renderer)
     73 finally:
     74     if artist.get_agg_filter() is not None:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:3034, in _AxesBase.draw(self, renderer)
   3031     for spine in self.spines.values():
   3032         artists.remove(spine)
-> 3034 self._update_title_position(renderer)
   3036 if not self.axison:
   3037     for _axis in self._axis_map.values():

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axes/_base.py:2978, in _AxesBase._update_title_position(self, renderer)
   2976 top = max(top, bb.ymax)
   2977 if title.get_text():
-> 2978     ax.yaxis.get_tightbbox(renderer)  # update offsetText
   2979     if ax.yaxis.offsetText.get_text():
   2980         bb = ax.yaxis.offsetText.get_tightbbox(renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1336, in Axis.get_tightbbox(self, renderer, for_layout_only)
   1333     renderer = self.figure._get_renderer()
   1334 ticks_to_draw = self._update_ticks()
-> 1336 self._update_label_position(renderer)
   1338 # go back to just this axis's tick labels
   1339 tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2609, in YAxis._update_label_position(self, renderer)
   2605     return
   2607 # get bounding boxes for this axis and any siblings
   2608 # that have been set by `fig.align_ylabels()`
-> 2609 bboxes, bboxes2 = self._get_tick_boxes_siblings(renderer=renderer)
   2610 x, y = self.label.get_position()
   2611 if self.label_position == 'left':

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:2161, in Axis._get_tick_boxes_siblings(self, renderer)
   2159 axis = ax._axis_map[name]
   2160 ticks_to_draw = axis._update_ticks()
-> 2161 tlb, tlb2 = axis._get_ticklabel_bboxes(ticks_to_draw, renderer)
   2162 bboxes.extend(tlb)
   2163 bboxes2.extend(tlb2)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in Axis._get_ticklabel_bboxes(self, ticks, renderer)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/axis.py:1315, in <listcomp>(.0)
   1313 if renderer is None:
   1314     renderer = self.figure._get_renderer()
-> 1315 return ([tick.label1.get_window_extent(renderer)
   1316          for tick in ticks if tick.label1.get_visible()],
   1317         [tick.label2.get_window_extent(renderer)
   1318          for tick in ticks if tick.label2.get_visible()])

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:956, in Text.get_window_extent(self, renderer, dpi)
    951     raise RuntimeError(
    952         "Cannot get window extent of text w/o renderer. You likely "
    953         "want to call 'figure.draw_without_rendering()' first.")
    955 with cbook._setattr_cm(self.figure, dpi=dpi):
--> 956     bbox, info, descent = self._get_layout(self._renderer)
    957     x, y = self.get_unitless_position()
    958     x, y = self.get_transform().transform((x, y))

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:373, in Text._get_layout(self, renderer)
    370 ys = []
    372 # Full vertical extent of font, including ascenders and descenders:
--> 373 _, lp_h, lp_d = _get_text_metrics_with_cache(
    374     renderer, "lp", self._fontproperties,
    375     ismath="TeX" if self.get_usetex() else False, dpi=self.figure.dpi)
    376 min_dy = (lp_h - lp_d) * self._linespacing
    378 for i, line in enumerate(lines):

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:69, in _get_text_metrics_with_cache(renderer, text, fontprop, ismath, dpi)
     66 """Call ``renderer.get_text_width_height_descent``, caching the results."""
     67 # Cached based on a copy of fontprop so that later in-place mutations of
     68 # the passed-in argument do not mess up the cache.
---> 69 return _get_text_metrics_with_cache_impl(
     70     weakref.ref(renderer), text, fontprop.copy(), ismath, dpi)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/text.py:77, in _get_text_metrics_with_cache_impl(renderer_ref, text, fontprop, ismath, dpi)
     73 @functools.lru_cache(4096)
     74 def _get_text_metrics_with_cache_impl(
     75         renderer_ref, text, fontprop, ismath, dpi):
     76     # dpi is unused, but participates in cache invalidation (via the renderer).
---> 77     return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backends/backend_agg.py:213, in RendererAgg.get_text_width_height_descent(self, s, prop, ismath)
    211 _api.check_in_list(["TeX", True, False], ismath=ismath)
    212 if ismath == "TeX":
--> 213     return super().get_text_width_height_descent(s, prop, ismath)
    215 if ismath:
    216     ox, oy, width, height, descent, font_image = \
    217         self.mathtext_parser.parse(s, self.dpi, prop)

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/backend_bases.py:652, in RendererBase.get_text_width_height_descent(self, s, prop, ismath)
    648 fontsize = prop.get_size_in_points()
    650 if ismath == 'TeX':
    651     # todo: handle properties
--> 652     return self.get_texmanager().get_text_width_height_descent(
    653         s, fontsize, renderer=self)
    655 dpi = self.points_to_pixels(72)
    656 if ismath:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:363, in TexManager.get_text_width_height_descent(cls, tex, fontsize, renderer)
    361 if tex.strip() == '':
    362     return 0, 0, 0
--> 363 dvifile = cls.make_dvi(tex, fontsize)
    364 dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
    365 with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:295, in TexManager.make_dvi(cls, tex, fontsize)
    293     with TemporaryDirectory(dir=cwd) as tmpdir:
    294         tmppath = Path(tmpdir)
--> 295         cls._run_checked_subprocess(
    296             ["latex", "-interaction=nonstopmode", "--halt-on-error",
    297              f"--output-directory={tmppath.name}",
    298              f"{texfile.name}"], tex, cwd=cwd)
    299         (tmppath / Path(dvifile).name).replace(dvifile)
    300 return dvifile

File /opt/hostedtoolcache/Python/3.9.19/x64/lib/python3.9/site-packages/matplotlib/texmanager.py:254, in TexManager._run_checked_subprocess(cls, command, tex, cwd)
    250     report = subprocess.check_output(
    251         command, cwd=cwd if cwd is not None else cls._texcache,
    252         stderr=subprocess.STDOUT)
    253 except FileNotFoundError as exc:
--> 254     raise RuntimeError(
    255         f'Failed to process string with tex because {command[0]} '
    256         'could not be found') from exc
    257 except subprocess.CalledProcessError as exc:
    258     raise RuntimeError(
    259         '{prog} was not able to process the following string:\n'
    260         '{tex!r}\n\n'
   (...)
    267             exc=exc.output.decode('utf-8', 'backslashreplace'))
    268         ) from None

RuntimeError: Failed to process string with tex because latex could not be found
<Figure size 640x480 with 1 Axes>

Wrapping up#

In this notebook, you compared two possible states for a ball rolling on a hemisphere: contact and no contact. You used free body diagrams, kinetic diagrams, and the chain rule to find the transition between contact and no contact.

You used scipy.optimize.fsolve to solve for when a function is 0.