All Questions
Tagged with conservation-laws rotational-dynamics
178
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Conservation of linear vs. angular momentum in two similar cases
I have a question that eludes my understanding:
Imagine we have a bullet of mass $m$ and a rigid pendulum with a bob of mass $M$ hanging from a rigid rod of negligible mass hanging from the ceiling ...
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Does moving the idler in a wheel and disk CVT conserve energy or momentum? [closed]
Consider the wheel and disk CVTs (continuous variable transmissions) below. Configuration A comprises a CVT disk coupled to the "system under control" 's', whereby a control wheel 'cw' ...
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How can we choose two different mass moment of inertias for the same momentum calculation?
I am working on answering part (a) and here is what I got:
By conserving linear momentum, we have that $$mv_0 =(3M)v_f \hspace{3mm}\implies \hspace{3mm} v_f =\frac{1}{3}v_0$$ Now, in order to conserve ...
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Proof for conservation of angular momentum in rotating frame of reference
imagine a simple situation such that an object is rotating on a table about a rope as seen in the below figure
now if i pull on the rope from the center , the radius of circular motion of the object ...
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"Momentum" of spinning disc from collision -- conserving momentum of input momentum?
I have an application for which I have concluded a collision lets conserve momentum.
Examples of the type of scenario in which I believe my conclusion applies:
a waterwheel blade hit by a ball (wheel ...
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Infinite angular velocity paradox
This paper is based on a question by Puk asked Jun 28, 2020 on the Stack Exchange Physics site, Newton's 2nd law for rolling motion with changing moment of inertia, about a long, hollow, rigid but ...
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Rotational quantum states for atoms
It is well-established that molecules possess rotational and vibrational quantum states, due to molecular symmetries, in addition to electronic states. In contrast, it is generally accepted that atoms ...
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Momentum conservation laws and explanation
I understand that momentum can be conserved along a certain axis while not along another. If there are forces that are affecting our system in the axis we are interested in that means the momentum ...
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Which Potentials lead to Kepler's second Law?
Which type of potentials lead to Kepler's second law "same area in same time"?
$$dA=\frac{1}{2} \vec{r} \times \vec{dr}.$$
$$\frac{dA}{dt}=c=\vec{r} \times \frac{\vec{dr}}{dt}=\vec{r} \...
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Can a stationary object acquire angular momentum? [closed]
I'm very confused about the concept of "spin", the "inherent angular momentum" of an object. Will any object other than elementary particles acquire spin when it's completely ...
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How does conservation of angular momentum work when a body is rotating on multiple axes? [duplicate]
I'm trying to understand how momentum is conserved when gymnasts twist mid-air while they are doing a flip. In this post, I will refer to the movement of his feet over his head as "rotation",...
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Breakage of a support during rotation [closed]
This is a trivial question and probably already asked elsewhere, but not being a native English speaker I struggle to use effective keywords.
In any case, we have a thin homogeneous rod resting on a ...
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Mathematical Proof of consistency of centre of mass in a Rigid body
I read that the center of mass remains unchanged in its position with respect to other points in the rigid body, even when any external force is applied to the body. However, I am willing to know if ...
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Conservation of Angular Momentum, why does person rotate only one way?
As seen from the video that i linked, when the wheel is spinning then he doesnt rotate, but as soon as he flips the wheel he will start to rotate. Why he doesn't rotate both counter and anticlock wise?...
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Why a spinning top bounces in a direction vertical to the surface that it hits?
When a spinning top slowly advances and hit a surface (a wall), intuitively one would expect that the top gets bounced mostly along the wall, due to the friction between the top and the wall. But the ...
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