All Questions
Tagged with conservation-laws angular-momentum
462
questions
1
vote
2
answers
147
views
Doubt on conservation of angular momentum for Kepler's laws
Just before proving Kepler's laws, my Professor claimed that if $\vec{F}$ is a central force with center $O$ and it is the only force acting on a point $P$, then the trajectory of $P$ is a curve plane....
- 13
1
vote
0
answers
33
views
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' ...
2
votes
3
answers
235
views
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 ...
1
vote
1
answer
41
views
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 ...
1
vote
3
answers
49
views
How is momentum conserved in this collision with loosely-connected spheres?
There are three identical spheres. B and C are loosely connected with a light inextensible string, and A approaches B directly at some initial velocity $v$. There is no angular momentum.
A and B have ...
- 5,148
0
votes
0
answers
19
views
Does the direction of an angular velocity vector always stays constant with no force involved [duplicate]
Are there cases where there is a rigid body that rotates somehow and the direction of the angular velocity vector changes in the lab system?
- 101
0
votes
1
answer
83
views
"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 ...
- 19
0
votes
3
answers
77
views
Rolling in opposite direction to linear motion
In this blog about a cylinder rolling up a frictionless incline, the author concludes that the cylinder will still be spinning clockwise at the top of its ascent up the hill and will then descend with ...
- 6,102
13
votes
3
answers
2k
views
Proving Kepler's second law of planetary motion using conservation of angular momentum: What about gravity from other planets?
I'm reading An Introduction to Mechanics by Kleppner and Kolenkow. In the chapter on angular momentum, a (beautiful!) example is given by discussing Kepler's second law of planetary motion.
The law ...
- 605
0
votes
0
answers
20
views
Why angular momentum keeps the giroscope standing in "impossible" orientations?
I am trying to understand how gyroscopes can maintain rotation in different "impossible" orientations when spinning.
I saw that the behaviour in zero-g is slightly different. On Earth, the ...
0
votes
2
answers
133
views
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 ...
- 33
6
votes
3
answers
1k
views
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} \...
- 101
1
vote
3
answers
68
views
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 ...
0
votes
1
answer
86
views
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",...
0
votes
0
answers
83
views
Conservation of angular momentum in particles reactions
In particles or nuclear reactions the square modulus of total angular momentum (the sum of spin and orbital angular momentum) is conserved.
When calculating the density of states to compute cross ...
- 338