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[Coop and Dino singing]

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When we think of waves, our first thought might be the ocean: those big, beautiful waves [Man surfboarding on a wave]

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are the dreams of surfers…

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…and the nightmares of sandcastle builders.

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But there are plenty of other kinds of waves, like the sound waves produced by sandcastle

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builders as they curse the cruel, cruel ocean. [Man cursing the waves crushing his sandcastle]

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But before we dive into waves…

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…we're going to learn about two important parts of every wave: frequency and amplitude.

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The frequency of a wave is the number of times its wave pattern repeats in a given amount [Coop discussing frequency of waves]

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of time.

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So over some amount of time, a high frequency wave will speed by, and repeat its wave pattern

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a bunch of times.

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On the other hand, a low frequency wave will seem sluggish by comparison, repeating its

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wave pattern fewer times.

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Aw…looks like this wave could use a nap. [Low frequency wave reading]

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The amplitude of a wave is the distance from its rest position to its highest point. [Dino teaching about amplitude of waves]

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The higher the energy of the wave, the higher the amplitude, so while a high-energy wave

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will have an amplitude that reaches for the stars…

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…a low-energy wave will barely be able to reach the cupboards.

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Which is a shame…that's where all the best snacks are kept! [Cupboard opens and snacks appear]

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Okay, now that we've covered frequency and amplitude, it's time to dive into waves!

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Appropriately, we'll start with water waves!

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Many water waves are caused by wind whipping up the water… [Wind creating the waves]

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…but some are created by the gravitational pull of the moon.

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And you thought all the moon did was sit up in the sky and look pretty.

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Next on our wave list?

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Sound waves.

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In the same way that water waves are vibrations of water…

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…sound waves are vibrations of air.

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Sound waves move crazy fast, at 330 miles per second. [Coop discussing sound wave facts]

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Usain Bolt, eat your heart out.

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Sound waves travel through the air, so they can't travel in a vacuum.

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Not that anyone would want to travel in a vacuum…can you imagine the dirt and dust, [Musical note trying to get inside a vacuum]

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and…oh, not that kind of vacuum.

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Gotcha.

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Ahem.

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So outer space is a pretty quiet location.

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You might have to worry about running out of oxygen, but hey, you don't have to worry [Man floating in space]

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about loud neighbors.

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If you're on our wavelength, you know what we'll be discussing next…

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…Earthquakes!

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Sometimes huge masses of the Earth's surface try to move past each other, but can't.

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How rude.

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As they push and push, friction and energy build up between them… [Earth plates bumping into each other]

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…until all that energy gets released at once, as seismic waves that ripple through

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the Earth's crust.

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These seismic waves can cause all sorts of trouble, like avalanches and tsunamis.

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Another kind of wave comes from lasers. [Dino discussing laser waves]

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"Laser" stands for "Light Amplification by Stimulated Emission of Radiation," which does

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have a certain ring to it, but "laser" is a bit catchier.

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Lasers emit light, but unlike a flashlight, that throws light waves all over the place, [Man in the dark turns on flashlight]

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willy-nilly…

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…a laser beam keeps waves tightly together.

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Lasers are used all over the place, from electronics to medicine to metalwork.

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Good luck using a flashlight to perform a surgical operation.

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We also see waves used in the exchange of information.

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In telecommunications, carrier waves are high-frequency waves that convey information. [Coop discussing telecommunications]

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For a long time, analog signals were the only game in town: smooth, continuous waves that

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were used to broadcast stuff like radio and TV.

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But more recently, digital signals have become more popular.

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Unlike the continuous analog waves…

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…digital waves only capture discrete bits of information, making them blockier in appearance.

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However, since you're probably watching what's on TV instead of readout of the waveforms [Girl watching TV]

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of the information going into your TV, you probably won't notice.

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And if you are reading the information waveforms, then remind us not to discuss last night's

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episode around the water cooler with you. [Man and woman talking by the water cooler]

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