Angular Momentum: Equations for Angular Velocity & Point Mass

Click For Summary
Angular momentum can be expressed in terms of angular velocity using the equation L = Iω, where L is angular momentum, I is the moment of inertia, and ω is angular velocity. For a point mass moving along the circumference of a circle with tangential speed v, the angular momentum is given by L = mvr, where m is the mass, v is the tangential speed, and r is the radius of the circle. The moment of inertia for a point mass is I = mr², but this is not directly related to angular momentum. The discussion clarifies the distinction between moment of inertia and angular momentum. Understanding these equations is crucial for solving problems related to rotational motion.
mogley76
Messages
17
Reaction score
0

Homework Statement



give equations for angular momentum in terms of :
1. angular velocity
2. a point mass moving along the circumfrence of a circle with a tangential (linear) speed v.

Homework Equations



none

The Attempt at a Solution



1. is L= I w...angular vel = moment of inertia X angular velocity

2. I = mr^2im not too sure about the second one? can someone help??
 
Physics news on Phys.org
The second one is moment of inertia, not angular momentum. For the second one, just go back to the definition of angular momentum.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

Similar threads

Replies
5
Views
1K
  • · Replies 17 ·
Replies
17
Views
860
Replies
335
Views
16K
Replies
67
Views
4K
  • · Replies 45 ·
2
Replies
45
Views
4K
Replies
3
Views
1K
Replies
5
Views
3K
Replies
10
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
Replies
18
Views
7K