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Faraday Ice pail

This is PASCO demonstration that can be used to illustrate charge transfer by contact. The demonstration uses a Faraday ice pail, which basically consist of two isolated concentric cylinders made of a metallic mesh. In order to avoid charge induction from the environment on the inner cylinder, the outer cylinder must be connected to a good ground. The inner cylinder is connected to an electrometer ,which is more sensitive than our electroscopes and is able to measure tiny charges in the inner cylinder. Charge is induced in the inner cylinder when a charged object is brought inside it. The PASCO kit also provides a set of probes: one metallic and two made from different insulating materials. Rubbing the two insulating materials let them charged with opposite charges. The magnitude of the charge is enough to be detected by the electrometer even on rainy days. The metal probe can be used to sample charge density from a charge object. The electrometer output can also be send to a computer for processing, but I have not yet explored this capability.
ID: d0012
Set up time:
5 minutes in class.
Requires:
A good ground. Components.
Notes:
You may need assistance the first time you use this demo.The demo works even on rainy days. Rubbing the white and blue probes, produce enough charge to be measure with the electroscope. The electroscope is battery run, when you switch it on, check that the voltage range indicators(LEDs) light up in sequence, which indicates that batteries are OK. Connection of the outer pail cylinder to a good ground is very important to drain any induce charge from the environment.The alligator clips that connect the pail to the electrometer are color coded and are not connected to each other. The black goes to ground and the red to the electrometer measurement circuit.Before connecting the electroscope to the inner cylinder, ground that cylinder to remove any stray charge in it.After grounding the outer cylinder and removing any stray charge from the inner one, connect the electroscope and press the button to zero out the reading. Be careful not to touch the inner cylinder with the charged object. When probing a charged object using the metallic probe from the kit, make sure that the plane of the probe is tangent to the surface of the object.
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Table of Components

Qty. name location notes
1 Faraday ice pail
Cables: Male-BNC to alligator-clips W106; North Shelves; U2-L1 Clear plastic box clips are color coded: black to ground
1 Banana cable (black) for connection to ground.
1 Set of probes: 1 white, 1 blue, 1 aluminum W106; North Shelves; U2-L1 Clear plastic box