How To Build A Simple Transformer Coil

A transformer, a device in which a magnetic field couples two circuits while linked to each, converts one AC voltage to another. A transformer typically converts between high and low voltages. A step-up transformer raises voltage while a step-down transformer lowers voltage. The ideal transformer has a perfect magnetic coupling and all the power fed into the transformer is available at the output, but in reality there are losses. A demonstration transformer, made very easily, teaches the basic principles of a transformer.

Step 1

Use the wire stripper to strip the insulation off the end of a long piece of copper wire. Wrap it 30 times around a cylinder of soft iron to make the solenoid. Use the alligator clips to connect the two ends of the wire into a power supply. Connect a 6-volt bulb parallel with the solenoid to make a primary coil.

Step 2

Strip the ends off another long piece of wire. Wrap the wire 60 times around the same soft iron core to make the secondary coil.

Step 3

Connect the two bare ends from the second piece of wire to a 6-volt bulb.

Step 4

Turn on the power and join together the two soft iron cores to make the primary coil a powerful electromagnetic.

Step 5

Compare the brightness of the bulbs to see that the secondary is much brighter. Repeat with 15 turns on the secondary coil and everything is much dimmer.