Learn more physics!
How does a flashlight work?
- Staci smith (age 16)
First Coast Hs, jacksonville,fl,usa
As you probably know flashlights have batteries in them. what a
battery does is it uses a chemical reaction to put all the plus charges
on one side of the battery and all the minus charges on the opposite
side of the battery. Because like charges repel each other (want to get
away from each other) the minus charges don't like being all together
at one end of the battery. When we connect a wire from one end of the
battery to the other we give the minus charges (also called electrons)
a path they can flow through to get away from each other and get to the
plus charges on the other side. This is called a circuit. A flashlight
is a kind of circuit with a light bulb on the wire. A light bulb is
just a device that changes the energy of the moving minus charges into
light (it does this by getting hot and glowing brightly). Pushing down
on the switch of your flashlight connects the wire with the light bulb
to the battery and forms the circuit.
(republished on 07/28/06)
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