Mechanics:
Rotating Stool and Weights

PIRA Class: 1Q40.10

Purpose:
To demonstrate the conservation of angular momentum as the distribution of the rotating masses changes.

Description:
Spin on a rotating stool with a dumbbell in each hand.

1. Have a student sit on the stool and hold out to each side a dumbbell in each hand. (Student's vertical center of gravity needs to be in line with the rotational axis of the stool!)

2. Start the student rotating, SLOWLY!

3. Have the student slowly pull in the weights to their chest (as close as possible to their center of rotation).

NOTE:

• Choose a strong, slender student with long arms for maximum effect. The stronger the student - the greater the masses that they can hold outright.

• Let the student know that if they feel they start spinning too fast, they should extend the dumbbells out away from their bodies!

Equipment:
Rotating Stool and Dumbbells

Location:
Shelf 142 & 143