ENERGY CHANGES: More Forms of Energy

Now you're riding up a big hill. It's getting harder and harder to pump.

Some of the energy from your muscles makes the bicycle move, but some is converted into heat energy, which makes you want to unbutton your jacket. And some is getting stored in the bicycle itself. Puff-puff-puff-puff, finally you reach the crest of the hill. The potential energy in the bicycle can be released. You stop pedaling and coast down the hill. If the wind is at your back, it gives you a little extra push.

As you're biking, a car passes. The car doesn't rely on muscle power. It gets energy by burning a fuel, probably gasoline, to release the chemical energy in the fuel.

Even More Forms of Energy

Back at home, you turn on a radio It runs on electrical energy which travels along the wires that connect a power plant to your home. The electrical energy used by the radio is converted into sound energy.

Sound is another form of kinetic energy--it's air in motion. You can move your muscles to make sound too. For example, you can hit a drum, sing or shout, or strum on a guitar. The guitar strings, vocal cords, or drumhead, once set in motion, make the air around them move.

NEXT: How do we use electrical energy?