All Questions
Tagged with relative-motion rotational-dynamics
16
questions
4
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Angular momentum about a moving point
I was used to see the Angular Momentum Principle as:
$\dot{\underline{H}_O} = \underline{M}_O^{ext}$
that is, the change in angular momentum equates the external torque w.r.t. a point $O$.
Now, I'...
3
votes
2
answers
60
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Why don't hovercrafts move West relative to the Earth [duplicate]
Suppose that there is a hovercraft floating a few centimetres above the Earth's surface. As it is disconnected from the Earth, which is spinning from West to East, shouldn't it appear to move East to ...
2
votes
4
answers
3k
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Why does hot air balloon rotate with the earth?
This might be a silly question but I have been wondering this for quite a while.
When a hot air balloon is flying in the sky, the earth is rotating at the speed of 1000 mph. Why does it move along ...
2
votes
1
answer
116
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Why ball fall at same location from where we throw it? [duplicate]
I have a silly question. As we all know earth is rotates at a speed of 460 m per sec. So if I throw a ball in the air for 10 sec than the ball must fall 4600 m away from me but these does not happen ...
1
vote
1
answer
120
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Centrifugal force in inertial systems
My textbook gives an example:
There are two systems, $O$ is inertial and $O'$ non inertial. $O'$ is rotating whit $\omega=\mathrm{constant}$ and $O=O'$.
We assume that a disc is rotating whit the ...
1
vote
2
answers
2k
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Directions of static & kinetic friction?
Static friction :
Static friction opposes relative motion between two surfaces. The car is moving at some tangential velocity relative to the road. Thus, static friction should act in the opposite ...
1
vote
2
answers
147
views
Relativity of velocity while riding a bike
I was trying to think of a situation in which an observer would be able to determine whether he is moving or not. Since velocity is a relative quantity I was unable to do so.
However, consider a ...
0
votes
1
answer
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Since Earth spins, would an aircraft travelling opposite to direction of Earth spin take less time? [duplicate]
Suppose we want to reach the point on earth which in relative terms is exactly on the opposite end of the sphere we call earth (I know it is not an exact sphere).
We either dig vertically downwards, ...
0
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3
answers
2k
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Explain the relative motion between two particles of a rotating rigid body
A rigid body is defined as a collection of particles in which distance between each pair of particles remains constant.
I was taught that the motion of any one particle of the rigid body with respect ...
0
votes
1
answer
54
views
To find the displacement of a rolling body
When calculating the displacement of a rolling body do we just calculate the displacement due to Vcom in a particular time t or additionally need to consider also the displacement that may be produced ...
0
votes
3
answers
69
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Time Dilation and Spinning Reference Frames
If a spaceship approaches a rapidly spinning planet, would the planet's inhabitants , the inhabitants of the planet where the spaceship came from , and the spaceship's occupants observe time dilation ...
0
votes
0
answers
105
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Is there a bug in this step (and how to fix it?)
Reading an old book of classical mechanics (Spiegel's theoretical mechanics) I came across a passage that I would like to clarify. In order to find the equations of motion of free falling point ...
0
votes
1
answer
141
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Can we move without moving? [duplicate]
So here is the question,
If I jump and hover over the ground for sometime why don't we move away from the point I jumped from? Because earth is rotating so if I hover long enough we should move from ...
0
votes
1
answer
240
views
How would one compute the path of an particle's motion from forces defined in different frames of reference?
I'm trying to write a computer program to render and play-back the path of a particle existing in 2D space given all forces acting on said particle. This is relatively easy to do if all forces are ...
0
votes
0
answers
831
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Simple Rotating frame of reference
I have a car moving in straight line with certain time-varying acceleration and there is another car moving in a curvilinear way along some curved path with some time-varying acceleration. The ...