Current Balance Apparatus

 

Current Balance Apparatus

 

Code Number: 5H40.40

Demo Title: Current Balance

Condition: Excellent

Principle: Magnetic Fields Around Current Carrying Wires

Area of Study: Electricity & Magnetism

Equipment: 

Variac, 6 Volt - 15 Amp Transformer, Amp Meter, Current Balance Apparatus, Laser.

Procedure:

Arrange the apparatus as shown. Adjust the balance so that it moves freely and the top wire is just balanced above but not resting on the bottom wire. Adjust the pitch of the mirror so that the laser reflection will show clearly on the classroom screen. Turn up the Variac but watch the amp meter and do not exceed 15 amps. The parallel wires will repel each other farther as more current is applied. The laser reflection may be observed and/or measured.

References:

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