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Contents of this post

## Development of rotational kinetic energy and moment of inertia

Remember to watch the video as if you were watching a lecture, but one you can pause, rewind, etc. As you watch the video, take notes and make sure you write down questions you have.

Try out the egg carton hands-on activity at home!

Remember: Moment of inertia (I) can also be thought of as the ‘rotational mass.’

### Sample Problems

#### Sample problem 1

Three 20.0-gram masses are 9.4 cm from an axis of rotation and rotating at 152 revolutions per minute. What is the moment of inertia of the three-object system? The strings holding the masses are of negligible mass.

#### Solution video

#### Sample problem 2

Two equal mass eggs are placed at either end in an egg carton of negligible mass. The egg carton is initially rotated about its middle. If the egg carton is now rotated about one end, what is the final moment of inertia of the eggs relative to their initial moment of inertia?

#### Solution video

## Homework

Well, isn’t everything homework now?

### TheExpertTA

Look for the assignment **3/30: Week three**

## Textbook

Coming soon!