Disturbing Behavior

Lift up your foot and stamp the floor. Feel that vibration? Hear that sound? Congratulations--you just produced some mechanical waves.

Of course, not all mechanical waves are created equal. Ocean waves can carry a surfer for yards. Sound waves can be loud enough to damage hearing. And the seismic waves caused by earthquakes can crumble buildings and bridges within minutes.

Watch this video to find out more about different types of mechanical waves, and the disturbances that cause them. Then, answer the question in the Take Notes box, below. You may read the transcript to the video, and watch the segment, as many times as you like.

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Disturbing Behavior Transcript

Ever been in an earthquake? Although we do get a dozen or so per year in North Carolina, it’s not an everyday danger here, like it is in other states.

But no matter where they hit, and how high up the Richter scale they go, scientists can use the seismic waves earthquakes produce to find out where they began.

Seismic waves are a type of mechanical wave. They carry the earthquake’s energy through the ground. Mechanical waves can also carry energy through the air, or the water.

As long as there’s something there—a medium—that they can move through, mechanical waves are behind the energy we hear, ride, feel, and run from.

WHAT YOU'LL DO

In this lesson you’ll learn some basic information about mechanical waves. You’ll watch a short video and then three animations that explain the nature and characteristics of mechanical waves, as well as the specific features of seismic waves, which are the waves produced by earthquakes. After taking notes and online quizzes, you’ll have a chance to review and organize what you’ve learned. Then you will produce your own project in which you'll define and describe mechanical waves.

Take Notes

What types of waves did you see in the segment, and what kind of disturbances might have caused them? Note them here. (Click SAVE when you have finished. To see your saved or submitted work again, click MY WORK at the top of the page.)