Science Project on an Electric Bell

Older phones use bells similar to the one we'll be building.
••• sunstock/iStock/Getty Images

The function of an electric bell relies on two things: the opening and closing of a circuit and an electromagnet. When power is running through the electric bell's circuit, an electromagnet draws a mounted metal clapper towards the bell, striking it. However, when the clapper is pulled by the electromagnet, it breaks the bell's circuit. No longer drawn in by the electromagnet, the clapper then falls back to its resting position. Back at the resting position, the clapper again completes the circuit, causing the current to pass back through the electromagnet, which once again draws the clapper toward the bell.

Building the Bell

    Wrap the magnet wire around one of the nails and sand off any insulation from either end of the wire. This will be our electromagnet.

    Slide the electromagnet through a hole in one upright of the wooden U.

    Using a wood screw, mount the metal clapper into the bottom interior of the wooden U in such a way that the hammerhead can freely move back and forth. Then, connect one wire end from the electromagnet to the bottom of the clapper.

    Slide the other nail through a hole drilled into the other upright of the wooden U and attach a standard electric wire to it.

    Attach the standard wire from the nail to either the positive or negative end of the two AA batteries connected in series. Attach the free wire from the electromagnet to the other end of the batteries.

    Mount the entire setup so that it lies flat on the wooden board and allows room for the bell to be mounted near the head of the clapper. Adjust both the nail and the electromagnet so that the clapper rapidly oscillates back and forth.

    Mount the bell on the wooden board so that the clapper repeatedly strikes it when the circuit with the electromagnet is complete.

    Things You'll Need

    • A small bell
    • A makeshift clapper (a strip of metal with a tiny hammerhead on one end)
    • 10 meters of 28-gauge magnet wire
    • Standard electrical wire
    • 2 AA batteries
    • Several wood screws
    • 2 4-inch nails
    • Small wood blocks in a U shape
    • A wooden board


    • Use additional wood screws to mount wires to the wooden frame.


    • Never power your homemade bell with an electrical outlet.

Related Articles

How to Make an Electrical 'Jacob's Ladder'
How to Build a DC Generator
Example of a Parallel Circuit
What Is a Magnetic Switch?
How Does a Solenoid Work?
How to Make a Doorbell for a Science Project
How to Make an Electric Stimulator With Speaker Wires
How to Make Electricity Flow Like Lightning Between...
Parts of a Motor
How to Mount a Circuit Board in an Electronic Project...
How to Build a Buzzer for a Science Project
How to Make an Electrical 'Jacob's Ladder'
How to Make a Burglar Alarm for Kids
How to Build an Electric Motor From Scratch
Basic Parts of a DC Generator
How to Make a Homemade Magnetic Levitation
How to Create Electrical Interference
Information for Kids About Electromagnets
What Is a Ferrite Clamp?
How to Use a Magnet to Create Electricity