Angular Momentum: Torque, Newton's 2nd Law, Rigid Body

AI Thread Summary
The discussion focuses on the relationship between torque and angular momentum for a rigid body rotating about a fixed axis. Torque is defined as the rate of change of angular momentum, which can be expressed as the cross product of the position vector and linear momentum. The connection to Newton's Second Law for linear momentum is established, highlighting that torque is analogous to force in linear motion. Participants seek clarification on deriving expressions for angular momentum in this context. Understanding these relationships is crucial for solving problems involving rotational dynamics.
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Homework Statement



A rigid body is free to rotate about a fixed axis k through the origin. A force F
is applied to the body at a point R. State the relationship between the torque due to
F and the angular momentum about the axis. How is this related to Newton’s Second
Law applied to linear momentum?

Homework Equations





The Attempt at a Solution



So i know that Torque = rate of change of angular momentum..

But Angular momentum = m(r x v) so how do i write an expression for it in this case?

Also how does it relate to NII for linear momentum?

THanks
 
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