Name: 3D Magnetic Fields
Category: Electricity and Magnetism
Subcategory: Magnetic Fields and Forces
Classes: PHYS 102/106, PHYS 309
Comments:
The electrophorus is a flat, 12 in. by 12 in. square piece of material which when rubbed with paper will produce a separation of charge. There are two types of electrophorus, one produces a net positive charge and the other produces a net negative charge. The pvc type electrophorus is dark grey in color and will produce a negative charge when rubbed. It is shown to the left in the photo above, with the paper towel marked with a circled "-" sign that is used to rub it. Acrylic is clear in color and will produce a net positive charge when rubbed. It is shown to the right in the above photo, with the paper towel marked with a circled "+" sign. A seperate paper towel is used to rub each material. Do not rub the different electrophoruses with the same paper towel because the conservation of charge dictates that the opposite charge will remain on the paper towel after it rubs one of the electrophorus's.
To get the charge off of the electrophorus a large, round metal plate with a handle is used to perform charge by induction. Hold the handle and place the plate onto the electrophorus after it has been charged by rubbing. While holding the handle carefully the outermost pinky finger to the electrophorus to induce the charges onto the metal plate. Thecharge on the metal plate can then be transported and used to perform electrostatic experiments.