What is the angular momentum of a rotating disk and how do you calculate it?

In summary, Angular Momentum is a physical quantity that measures the amount of rotational motion an object possesses. It is calculated by multiplying the moment of inertia by the angular velocity, and is related to torque by being directly proportional. The conservation of Angular Momentum is a fundamental law of physics that states that the total angular momentum of a closed system remains constant. Real-world examples of Angular Momentum include spinning tops, rotating planets, figure skaters, and fans.
  • #1
JSmithDawg
9
0

Homework Statement


The 1.8kg , 5.2-cm-diameter disk is rotating as shown. What is the angular momentum of the disk about the axle?

9-33.jpg

Homework Equations


L=Iω=(mr^2)ω

The Attempt at a Solution


r=.026m
m=1.8 kg
ω=600rpm*(1minute/60seconds)*(2pi radians/1rotation) = 62.83 rad/sec

L=(1.8kg * .026m^2) * 62.83 rad/sec = .076 (kg*m^2/s). I think this is correct, but my online quiz says that the answer is .038. What am I doing wrong?
 
Physics news on Phys.org
  • #2
What is the rotational inertia of the disk?
 

Related to What is the angular momentum of a rotating disk and how do you calculate it?

1. What is Angular Momentum?

Angular Momentum is a physical quantity that measures the amount of rotational motion an object possesses. It is a vector quantity, meaning it has both magnitude and direction.

2. How is Angular Momentum calculated?

Angular Momentum is calculated by multiplying the moment of inertia (a measure of an object's resistance to changes in rotational motion) by the angular velocity (the rate at which an object rotates around an axis).

3. What is the conservation of Angular Momentum?

The conservation of Angular Momentum is a fundamental law of physics that states that the total angular momentum of a closed system remains constant, even when external forces are applied. This means that if one part of a system gains angular momentum, another part must lose an equal amount of angular momentum.

4. How is Angular Momentum related to torque?

Torque is the force that causes an object to rotate around an axis. Angular Momentum is directly proportional to torque, meaning that the greater the torque applied to an object, the greater its angular momentum will be.

5. What are some real-world examples of Angular Momentum?

Some examples of Angular Momentum include a spinning top, a rotating planet, a spinning figure skater, and a rotating fan. In each of these cases, the object possesses angular momentum due to its rotational motion.

Similar threads

  • Introductory Physics Homework Help
Replies
26
Views
254
  • Introductory Physics Homework Help
Replies
3
Views
361
  • Introductory Physics Homework Help
Replies
9
Views
1K
  • Introductory Physics Homework Help
10
Replies
335
Views
9K
  • Introductory Physics Homework Help
Replies
3
Views
973
  • Introductory Physics Homework Help
Replies
6
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
2K
  • Introductory Physics Homework Help
Replies
8
Views
1K
  • Introductory Physics Homework Help
Replies
18
Views
2K
Back
Top