Electricity and Magnetism ** 5K30.20 ** Electromagnetic induction


Dissectible transformer


Theory: A transformer is used to change AC power from one voltage to another. Two coils are wrapped around an iron core. AC power running through one induces AC power in the other, with the ratio of voltages being the same as the ratio of the number of turns in the two coils, and inversely proportional to the ratio of currents.

Description: The Variac output should be set to about 10 V, and connected to one coil in the transformer via the suicide cord. Be careful to turn off the current before touching the suicide cord leads! The meter is used to measure the voltage in and out, giving either a factor of 4 increase or decrease depending on whether the 800-turn coil is used at the output or input stage.

Setup time: 10 minutes

References: (available in the demo room)