All Questions
24
questions
0
votes
3
answers
570
views
Find angular momentum using center of mass frame
Suppose I have a square-shaped plate getting hit by a ball as shown in the picture below (notice how the force vector applied by the ball is not parallel to the $r$ vector). Let's set the origin to be ...
- 147
3
votes
2
answers
934
views
Rotating Rod As a conical pendulum
Consider A Rigid Rod hinged at its top point Whirled around in a circle (similar to a conical pendulum). It is given that the angular velocity (and thus the semi-vertical angle) is constant. I am ...
- 1,295
2
votes
1
answer
332
views
Reference-frame transformation for the Lagrangian of a charged particle
The Lagrangian of a charged particle in a magnetic field reads:
$$
L=\frac{m}{2}\dot{\bf{r}}\cdot \dot{\bf{r}} + q\bf{A}\cdot \dot{\bf{r}}
$$
This is the Lagrangian in the reference frame $Oxyz$.
...
- 1,232
3
votes
2
answers
769
views
Confusions about frames of reference when deriving Euler's equation of rotational motion
I am getting confused about when torques should be frame independent. My understanding is that torque is the same in all frames that are rotating at constant angular velocity. However, this seems to ...
- 1,335
2
votes
1
answer
59
views
What is the physical argument for $d(G)_s = d(G)_b + d(G)_{rot} \quad ?$
In the book of Goldstein, Classical Mechanics, at the end of the page 171, it is stated that
A relation between the two differential changes in $G$ can be derived
on the basis of physical ...
- 2,283
0
votes
0
answers
404
views
Re: Susskind and Hrabovsky: Should the Lagrangian of a particle referred to a rotating frame omit the velocity dependent "potential"?
My question pertains to Lecture 6: Exercise 4 in The Theoretical Minimum by Leonard Susskind and George Hrabovsky. A suggested solution has been posted here: http://www.madscitech.org/tm/slns/
The ...
- 2,015
2
votes
1
answer
124
views
Applied Force in a Non-inertial Frame
Let us consider two reference frames: $S$ and $S'$. $S$ is an inertial frame and $S'$ is a non-inertial frame as it is rotating wrt $S$ with an angular velocity $\omega$ about a fixed axis. The ...
- 3,023
4
votes
1
answer
1k
views
Lagrangian of rotating springs
I'm trying to construct the Lagrangian for the following scenario. A turntable of radius $R$ is rotating at angular velocity $\omega$, maintained by a motor. Two springs with Hooke's constant $k$ are ...
user138458
18
votes
6
answers
9k
views
How can the centripetal force lead to objects flying apart?
I don't understand how the centripetal force, which always points to the center of our circular motion can cause this scenario:
We have a big stone which spins very fast, so fast that a part breaks ...
- 396