K2-26
Demonstrate the standard for mutual inductance.
A tall coil serves as the primary of a simple transformer. A smaller coil wraps around its center as a secondary. Switching the current in the primary on or off induces a calibrated voltage in the secondary. This can be displayed on a projection meter.

If desired, the roles can be reversed to show the effects; also, a center tap is available.,/p>

K1, K2, PW1