How To Make Movement Into Electricity

An electric generator transforms kinetic energy (energy of motion) into electrical energy.

Magnetic fields are produced by moving charges. A changing magnetic field through a loop of wire will induce a current in the wire. This basic principle underlies electric generators, power plants and wind turbines---the machines that generate the electricity so vital to our modern way of life. Turning movement into electricity is a simple and fairly straightforward experiment requiring magnets and a loop of wire. The stronger the magnets and the more turns of wire around the core, the more powerful your experimental generator will be.

Things You'll Need

• Fine copper wire
• Two magnets (same size)
• Tall narrow cardboard box
• Small light bulb (1.5 or 2 volt)
• Nail (long enough to reach all the way through the cardboard box)
• Spring type clothespin or hand drill (optional)

Instructions

1. Poke a hole through the center of the cardboard box using the nail. Insert the nail through the hole and place the two magnets on either side of it so they stick to the nail.

2. Wind the wire around the box. The more times the wire wraps completely around the box, the more powerful your generator will be. It is best that the wire loops be as close as possible to the point where the nail transects the box without actually coming in contact with the nail.

3. Connect each end of the wire to the light bulb. Don't use a regular 40-watt light bulb---you may not generate enough power to light it. Use a small 1.5 or 2 volt light bulb instead. This kind of bulb is available at stores like Radio Shack and may also be sold at some science supply stores.

4. Spin the nail as fast as possible so that the magnets rotate inside the box. If it's difficult to turn the nail quickly, attaching a spring type clothespin or use a hand-held drill. When the magnets are spun quickly enough, the bulb will light.

Tips & Warnings

• If the bulb does not light, it probably means the magnets are not turning quickly enough or the magnetic field they create is too weak to induce sufficient current. Try using stronger magnets.

• The generator described above is not powerful enough to cause a shock; nonetheless, always be careful when working with electricity.

• Never hold a magnet close to credit cards, cell phones, disks or any electronic devices. If you have a pacemaker, do not perform this experiment.

References

• Discover This: How Can You Make a Simple AC Generator?

Resources

• "Physics for Scientists and Engineers, Custom Edition"; Richard Wolfson and Jay Pasachoff; 1999.