Inertial frames and non-inertial frames videos
(i.e.,
Inertial frames and
and non-inertial frames
videos):
- Non-inertial Frames of Reference | 0:47:
The ball accelerates (i.e., follows a curved
path) even though no horizontal force
(other than
static friction
to cause rolling)
because it's in a
rotating reference frame
which is a non-inertial frame.
From the perspective of the approximately
inertial frame of the
ground, the
ball rolls in a straight line just as
Newton's 1st law of motion
says it should.
Both the
inertial forces
the centrifugal force
and the Coriolis force
are acting on the ball:
the first just by being in a
rotating reference frame
and the second because of moving relative to
the rotating reference frame.
Good for the classroom.
- Alien Abduction gravitron ride
at Bluegrass Fair Lexington (June 19th, 2021) | 2:14: Once the door closes, there is
NO ESCAPE.
Used to illustrate
the centrifugal force
which is the cause of the
latitude variation in
Earth's gravity g = 9.8 N/kg = 9.8 m/s**2 (fiducial value).
Apparently, the wall is tilted such that
there are 2
normal force
vector components:
a horizontal
component
that keeps you from going through the wall under the action of the
centrifugal force
and a vertical
component
that keeps you from sliding down the wall under the action of the
gravitational force.
Good for the classroom.
- Top 5 Space Experiments | 10:28:
There's a jump to the 4:20 mark.
The
International Space Station (ISS)
is a free-fall frame
(i.e., an exact inertial frame),
and so Newtonian physics
can be referenced directly to the
ISS frame
and everything behaves completely normally---except
for weightlessness of course.
Gravity is NOT turned off
in space.
In low-Earth-orbit,
gravity is almost the same as
on the Earth's surface, but
gravity pulls on everything equally
and nothing resists it: everything is in
free fall.
A few bits are good for the classroom.
- Guys Play Catch While Skydiving | 0:48:
Playing catch the way it should be done.
Because of
air drag,
varying air drag,
and probably some level of
clear-air turbulence,
the system of these
3 bold
skydivers is NOT an
exact inertial frame, but
it's NOT so far from one.
Local file: local link: frame_videos.html.
File: Mechanics file:
frame_videos.html.