Complete a Circuit

Print this page out and follow the directions to build your own circuit. Click on the 'Back' button to go back to Electrical Safety World.

In order for electricity to travel to where we need it, there must be a complete circuit of electrcity. A complete circuit is like a circle.

Electricity starts at a particular place, travels around the circuit, and returns to the same place.

Ask an adult to help you with this experiment.

Materials:

• 1 D-Cell Battery
• 1 1.2-volt lightbulb
• 1 E-10 lightbulb base
• 2 12-inch pieces of insulated solid strand copper wire (18-22 gauge), with one inch of insulation removed at each end
• masking tape

Directions:

1. Connect one end of each wire to the lightbulb base (see illustration).
2. Tape one free wire end to each end of the battery.

In this experiment, the complete circuit is something like the electrical distribution system that brings electricity to our homes. The battery produces the electricity like the generating plant does. What part of the distribution system is like the wires?

What happens if you only tape one of the wires to the battery? Why does that happen?