# Demo Detail

More with gyroscope (bike wheel)

Purpose:
To demonstrate the conservation of angular momentum.

Equipment:
Bike wheel Rope to attach to wheel Someone to hold rope or wheel

Equipment Location:
Other

Procedure:
The first part of this experiment is using the rope attached to the wheel. Start by spinning the wheel clockwise as if looking at the wheel from the side the rope is attached. Once the wheel is spinning allow the wheel to hang from the rope. The wheel should stay upright and start to rotate around the rope in a counter clockwise direction. The next part of this demonstration is to allow someone to hold the wheel by one handle. Again spin the wheel in a clockwise direction as the person holding the wheel sees it. Have the person rotate the wheel downward and as they do they should feel the wheel pushing to go to their left. If the person attempts to rotate the wheel up it should try to go to the right.

Hints:
When using the wheel have the student hold the side with the metal disc to avoid having their hand get into the spokes of the wheel. Also make sure that the wheel is spinning quite rapidly so that the effects can be clearly seen.

Relevant derivations/explanations:
For the first part of the experiment the wheel rotates counter clockwise because gravity is trying to rotate the wheel downward. Using the right hand rule you can see that by trying to rotate the angular momentum downward it creates a force to the left. This is the same force that exists when the wheel is rotated downward in the student's hand, when it goes to the left. The opposite is true when the wheel is rotated upward and it goes to the right.

##### Physics

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