Homemade Electric Generators

Project Designed by: Tina Daup, Heeyong Kang, Ryan Yates

This activity is designed to demonstrate a method of converting mechanical energy to electrical energy used in larger scale electric generators. Students will be split into teams to assemble a basic electric generator with loops of insulated copper wire, magnets, and a hand crank. The changes in magnetic flux produced by manually spinning the magnets in the center of several loops of wire will make current flow through the wires. Students will learn that mechanical energy can be converted to electrical energy by using the induced current to operate electronics such as light bulbs.

Electric Generators (basic explanation for students):

One simple way to think about a generator is to imagine it acting like a pump pushing water along. Instead of pushing water, however, a generator uses a magnet to push electrons along.

You will split into teams and assemble a basic electric generator with loops of insulated copper wire, magnets, and a hand crank. The changes in magnetic flux produced by manually spinning the magnets in the center of several loops of wire will make current flow through the wires. (This is a slight over-simplification, but it is nonetheless a very useful analogy.)

Materials needed (per generator):

• 1 hand crank
• 4 strong magnets
• Different lengths of wire for each team, in increments of 100ft.
• Small light bulbs
• 1 Multimeter
• 1 plastic cup
• Hot glue gun
• 4 inch nail
• 2 alligator clips
• Cardboard scraps

Procedure for students:

1. Using hot glue gun, melt 2 smooth circular holes into opposing sides of the plastic cup to fit the nail.

2. Leaving at least 6 inches of wire free, hot glue the beginning of the coils onto the plastic cup directly under one of the holes.

3. Loop the remaining wire around plastic cup, making sure to keep holes clear.

4. Hot glue the end of the wire after leaving at least 6 inches of wire free at the end on the same side as the beginning of the coils.

5. Strip about 1 inch of the ends of the wire.

6. Run nail through the holes in the plastic cup.

7. Separate magnets into groups of 2.

8. On one group of magnets, hot glue scraps of cardboard on outer edges so that the nail can fit in the middle of the two groups of magnets when they are put together.

9. Hot glue the group of magnets with the cardboard to the nail in the cup.

10. Hot glue the remaining group of magnets to the cardboard scraps on the first group so that the poles align.

11. Attach one end of the alligator clips to stripped ends of the wire and the other to a light bulb or multimeter.

12. Attach hand crank to nail and crank to generate current through wires.