If you think about it, mechanical waves are a disturbance caused by a disturbance. This is actually true of both mechanical waves and electromagnetic waves. Mechanical waves do require a medium -- a liquid such as water, a solid such as the ground, or a gas (or combination of gases , such as air) -- to carry energy from one place to another.
Watch this video to find out more about the nature of mechanical waves. As you watch the segment, you might want to check the definitions of specific terms. In addition to the glossary words listed above, the terms wave and particles will be described.
Stop the animation at any time, watch it again, or read the transcript.
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Waves are all around us. From the light we see, to the sound we hear, to the earthquake that shakes the ground. And the thing that makes a wave a wave is that it transports energy from one place to another. There are different types of waves (mechanical, electromagnetic) that transport energy through different environments (solid, liquid, gas, vacuum).
Sound, earthquakes, and waves in water are all mechanical waves, meaning they use a medium-- actual physical particles -- to pass the energy along.
The birth of a mechanical wave starts with a disturbance. Energy is applied to the medium and the particles of that medium bump, push, or pull against one another. These vibrations transfer the energy from one place to another while the medium it is transferred through stays put. Although the particles move back and forth, or up and down, or around in circles, they don’t actually change locations. It’s only the energy that travels -- and it can travel really, really far.
So when you hear that sound from afar, you can thank all the little particles that transferred that wave from there to here.
Write down three examples of mechanical waves, and the type of medium they travel through.