Try This at Home: Organic Battery
Electricity is the movement of tiny negatively-charged particles called electrons. Direct current electricity is when electrons are pushed in one general direction. A battery is an example of a direct current. Electricity has a wide range of uses, including turning motors and powering lights.
What You Need
- 1 lemon, grapefruit, potato, or apple
- 1 knife
- 2 pennies, preferably pre-1982
- 2 metal paper clips or galvanized nails
- Insulated wire
- Scissors or wire strippers (or sandpaper if wire is enamel-insulated)
- 1 LED bulb with exposed wires
What To Do
Make sure you have an adult with you to supervise this experiment.
Cut three lengths of wire, each about 20 cm (8 inches), then strip the insulation from the last 5 cm (2 inches) at every end. If your wire is enamel-insulated, use sandpaper to remove the insulation.
Cut the fruit or vegetable in half.
Wrap one end of the first wire around a penny and the other end around a paper clip. Stick the penny into one half of the fruit and the paper clip into the other half.
Wrap one end of the second wire around a penny and stick it into the half that already has a paper clip in it.
Wrap one end of the last wire around a paper clip and stick it into the half that has just the penny in it.
Touch the free ends of the wires from the fruit to the wires coming from the light bulb. If nothing happens, try switching which fruit wire touches which light bulb wire.
The juices in the fruit create a chemical reaction with the copper metal in the pennies and the zinc metal in the paper clips. The reactions cause electrons to be pushed through the wires, flowing in one direction from the pennies to the paper clips. This creates a direct current which lights up the light bulb when the electrons pass through it.
It's a myth that the rubber tires of a car insulate you from lightning. What actually protects you is the metal frame of the car that conducts the electricity around you.