Conductors and Insulators
Things You Will Need
- Dry cell battery
- Flashlight bulb
- Insulated copper electrical wire (Two 6-inch pieces, one 12-inch piece)
- Testing materials: metal screw, metal key, paper, plastic bottle cap, small block of wood, piece of cloth
- Cut three pieces of insulated copper electrical wire into two 6-inch pieces and one 12-inch piece.
- Have an adult strip the plastic insulation off the ends of each piece of wire to expose the copper wire.
- Wrap one end of the 12-inch wire and one end of a 6-inch wire around each of the poles on a dry cell battery.
- Wrap the free end of the 6-inch wire and one end of the remaining 6-inch wire around the base of a flashlight bulb.
- Touch the free, bare end of the 6-inch wire to the free, bare end the 12-inch wire. The light bulb should light up.
- One at a time, test the following items to determine which type of material is a conductor and which is an insulator: metal screw, metal key, paper, plastic bottle cap, small block of wood, and piece of cloth. Touch the free, bare end of the 6-inch wire
- Determine which items are conductors of electricity and which are insulators. The light will turn on with conductors, but will not for insulators.
What Should Have Happened
Metals are generally good conductors of electricity and will light the bulb. Non-metals will not conduct electric current and are called insulators. Insulators are valuable in helping us keep electricity from going where it is not wanted. This is why electrical wire is covered with a rubber, plastic, or cloth coating. Electricity will be conducted along the wire but not through the coating. Liquids, especially made with salts and acids, are also good conductors.
Webdate: June 11, 2002
Updated: July 2004
Comments/Whom to contact