Purpose: To demonstrate the forces between two parallel current-carrying wires.

The apparatus consists of a ring stand supporting two parallel wires and binding posts to which large pulsed currents may be applied. The currents may be chosen to run either parallel or antiparallel in these wires. A low voltage high current D.C. power supply provides the source of current. Car battery works better than D.C. power supply.

1. To demonstrate repulsion between the wires, the currents must run in opposite directions. To do this, merely remove the connector from the two binding posts on the lower end of the stand and then connect the D.C. power supply. It is important that the current be pulsed to 6 volts for only a few seconds, as a large amount of heat develops in the wires.
2. To demonstrate attraction between the wires, the currents must run in the same direction. This may be done by having both shorts connected at the top and bottom and then connecting a terminal of the power supply to the top binding post and the other to the bottom. Again, only pulse the currents.

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