EM6.3 Current Balance

This is two wires parallel to each other carrying current in the opposite directions. By the law of Biot-Savart, the magnetic field produced by each wire is equal in magnitude and in the same direction so that the wires repel each other. Placing a mirror on the edge of the top wire and pointing a laser at the mirror will show the repulsion on the lecture hall's side wall. Extensions of this could be discussions of the definition of ampere and the calibration of an ammeter. After plugging the apparatus in, allow it to warm the gallium swivel so that it can rotate easily.

Equipment Location: Shelf D1-3