Physics Demonstrations at Cal Poly Pomona
Demo Index:
Pira Index:
Title:
Description:
Demonstrates that charge is stored on the outside of a Faraday Ice Pail.
Equipment:
1. PVC electrophorus
2. Paper towel
3. Electroscope w/ pail (can) atop it
4. Charge transferring ball
Hand-out card of instructions (in pocket on back of this sheet) w/ equipment for this demo.
Procedure:
1. Charge the Ice Pail (can) with the electrophorus. (see hand-out card for instructions)
2. Alternately touch the transferring ball to the inside of the pail and then to your hand. After several repetitions, observe that nothing happens.
3. Repeat the transferring process, this time touching the ball to the outside of the pail. Notice the drain of charge (the electroscope leaf falls).
4. OPTION: Charge ball by induction (see hand-out card) and hold it in the center of the pail. Since the ball is charged oppositely from the pail, the electroscope shows more charge.
