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10 votes
2 answers
3k views

How can you solve this "paradox"? Central potential

A mass of point performs an effectively 1-dimensional motion in the radial coordinate. If we use the conservation of angular momentum, the centrifugal potential should be added to the original one. ...
user32109's user avatar
  • 521
3 votes
2 answers
2k views

Why does a body not rotate if force is applied on the centre of mass?

The definition of centre of mass on Wikipedia is given as This is the point to which a force may be applied to cause a linear acceleration without an angular acceleration. How can I prove that such ...
Manit Agarwal's user avatar
8 votes
9 answers
2k views

Different coordinate system as opposed to different reference frame

I'm having a hard time getting the difference between the two. In Euler's equations of rotating bodies for example, we have: $$ \mathbf{\dot{L}}+\mathbf{\omega} \times \mathbf{L} = \mathbf{\Gamma},$$ ...
Darkenin's user avatar
  • 1,038
10 votes
3 answers
3k views

Lagrangian equations of motion for ball rolling on turntable

The equations governing the motion of a ball of mass $m$, radius $R$ rolling on a table rotating at constant angular velocity $ \Omega $ which are derived using Newton's laws are: (I present these for ...
Kartashuvit's user avatar
3 votes
4 answers
675 views

Understanding the definition of tangent basis

This question could sound silly but I though a lot about it and I'm not new to physics. Let's say I have a plane on which I use polar coordinates, it means a point $P$ can be indicated by its ...
SimoBartz's user avatar
  • 1,904
2 votes
2 answers
12k views

When does not Newton's 3rd law apply?

Is Newton's 3rd law valid in non-inertial frames? If so, then are there other cases for which Newton's 3rd law is not applicable?
Revo's user avatar
  • 17.1k
0 votes
1 answer
70 views

Doubt in fictitious forces chapter in Morin

The question is this - I know 2 is what the non-inertial frame measures, but isn't $\frac{d\mathbf{A}}{dt}$ the real thing, the physical thing? And you can write that too in terms of the unit vectors ...
Neeladri Reddy's user avatar
0 votes
2 answers
189 views

Rotation of non-rigid bodies-centrifugal effect

Suppose that we have a bar of finite length which is rotating about its center of mass at a constant angular velocity in a horizontal plane. Gravity is neglected. The fact that the bar stretches ...
Ruslan Mushkaev's user avatar