PURPOSE: Used to illustrate the geometry for a final exam problem in electricity.

DESCRIPTION: A nylon filament fishing line in the process of its manufacture becomes charged with static electricity. Consider a long filament moving between two pieces of machinery (e. g., from spinneret to spool) at a velocity of 12 meters per second. Assuming that the filament carries a static charge of -10^-8 coulombs per meter of its length, find the electric field and the magnetic filed at a distance of 10 cm from the moving filament. Show their directions in a sketch. If you did not compute the electric and magnetic felds directly from Maxwell's equations explain how this could be done.

An electroscope is used to show that the film really is charged.


REFERENCES: (PIRA unavailable.)

EQUIPMENT: 16mm film rewinder with take-up reel and electroscope.

SETUP TIME: 10 min.

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