What is the Moment of Inertia of a Flywheel?

In summary, moment of inertia is a measure of an object's resistance to changes in its rotational motion. It can be calculated by adding up the products of each mass element in an object multiplied by the square of its distance from the axis of rotation. The formula for moment of inertia is I = Σm*r^2 and the units depend on the units used for mass and distance in the formula. Moment of inertia affects rotational motion by determining how much torque is needed to cause a certain angular acceleration, with larger values requiring more torque for the same rate of rotation.
  • #1
deltas
7
0

Homework Statement


The work done in accelerating a flywheel from rest to an angular speed of 14.5 revolutions per second is 22.0 kJ. What is the moment of inertia of the flywheel?

Homework Equations


½Iω² = 22.0 kJ

The Attempt at a Solution


½Iω² = 22.0 kJ
I = (2)(22.0 kJ)/ω²
ω = (14.5 revs/sec)
= (14.5 revs/sec) × (2π rad/rev)
= 29π = 91.1

I = (2)(22)/(91.1)2
I = 44/8300.3
I = 0.00531
 
Physics news on Phys.org
  • #2
You are using SI units. How many joules are there in 22kJ?
 
  • #3
Oh, thank you! I hadn't even noticed!
 

Related to What is the Moment of Inertia of a Flywheel?

1. What is moment of inertia?

Moment of inertia is a measure of an object's resistance to changes in its rotational motion. It depends on the mass distribution of the object and the axis of rotation.

2. How do you calculate moment of inertia?

Moment of inertia can be calculated by adding up the products of each mass element in an object multiplied by the square of its distance from the axis of rotation.

3. What is the formula for moment of inertia?

The formula for moment of inertia is I = Σm*r^2, where I is the moment of inertia, Σm is the sum of the masses of all the individual elements, and r is the distance from each element to the axis of rotation.

4. What are the units for moment of inertia?

The units for moment of inertia depend on the units used for mass and distance in the formula. In the SI system, the units are kg*m^2.

5. How does moment of inertia affect rotational motion?

Moment of inertia affects rotational motion by determining how much torque is needed to cause a certain angular acceleration. Objects with larger moment of inertia will require more torque to rotate at the same rate as objects with smaller moment of inertia.

Similar threads

What is the moment of inertia of the flywheel?
    • Introductory Physics Homework Help
Replies
4
Views
8K
What is the "r" in the moment of inertia?
    • Introductory Physics Homework Help
Replies
13
Views
2K
Rotational Motion and moments of inertia
    • Introductory Physics Homework Help
Replies
9
Views
2K
What Are the Units for Precession Rate (Ω)?
    • Introductory Physics Homework Help
Replies
5
Views
1K
What is the torque exerted by the flywheel on the machine?
    • Introductory Physics Homework Help
Replies
5
Views
3K
Calculation of torque to stop a wheel.
    • Introductory Physics Homework Help
Replies
4
Views
5K
Moment of Inertia: Disk 1 & 2 Homework
    • Introductory Physics Homework Help
Replies
1
Views
2K
Moment of Inertia with pulley and two masses on a string (iWTSE.org)
    • Introductory Physics Homework Help
Replies
8
Views
9K
Moment of inertia, center of mass and vincular reaction of a rod
    • Introductory Physics Homework Help
Replies
16
Views
2K
Moment of inertia of a suspended cylinder
    • Introductory Physics Homework Help
Replies
5
Views
2K

Hot Threads

Recent Insights

Back
Top