1. Make waves of different sizes.
Use the Wave Simulator to make waves of different sizes. Look at how each affects a boat at rest, in an area with no current. Use the toolbar to change the wave height, or how tall waves are. Use the toolbar to change the wavelength, or how far apart the waves are. Use the toolbar to change the wave period. How do those changes affect the waves? How do they affect the boat?

2. Talk about the experience.
What did you have to change to make the waves bigger? Smaller? Faster? Slower? What did you have to change to make lots of waves? A few?

Quiz Yourself!

What is wave height?

Show Answer

Wave height is how tall waves are.

What You’ll Need


Background Information

Waves are the movement of water. Watching the movement of waves helps you to understand their patterns.


Term Part of Speech Definition Encyclopedic Entry



the top of a wave.



steady, predictable flow of fluid within a larger body of that fluid.

Encyclopedic Entry: current



moving swell on the surface of water.

wave height


the distance between a wave's trough and crest.



the distance between the crests of two waves.

wave trough


the lowest part of a wave.

Learn More


Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.


Ruth A. Musgrave


Christina Riska, National Geographic Society

Expert Reviewer

Julie Brown, National Geographic Society


adapted from National Geographic Xpeditions lesson “Introduction to Waves”

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