All Questions
5
questions
8
votes
3
answers
335
views
Apparent violation of the law of conservation of angular momentum in the torques experienced by two interacting electric dipoles
Question
Consider two dipoles $({p_1}\hat{i}$ and ${-p_2}\hat{j})$ kept in the $x-y$ plane at $(0,0)$ and $(d,0)$ respectively. Calculate the torque about the COM.
Approach 1
Suppose we select the COM ...
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 ...
0
votes
2
answers
493
views
Centre of Mass and Reference Point
When calculating the centre of mass for a small body compared to the earth, the equation
$$\vec r_c = \frac {\sum_i m_i \vec r_i} {\sum_i m_i}$$
is used, where $\vec r_c$ is the position vector for ...
0
votes
5
answers
160
views
Torque Intuition [duplicate]
We are all taught that the torque $\boldsymbol{\tau}$ is given by $\boldsymbol{\tau} = \mathbf{r}\times\mathbf{F}$ so that torque increases with the lever arm length. What is the physical intuition ...
0
votes
1
answer
344
views
Torque about an accelerating pivot
Let's say that the torque equation about the pivot (in the pivot's frame of reference) is shown below:
$$k\sin\phi=I\ddot\phi$$ where $k$ is some arbitrary constant.
However, the pivot point is ...