ShmoopTube

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Thank you We sneak And here's your shmoop to use

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your brought to you by traveling waves Of course our

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favorite way to travel waves is by hanging ten on

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a sweet surfboard were goofy footed Well by hanging ten

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we mean ten fingers clutching the board Yeah surfing is

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scary We've seen jaws and we know what's in the

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oceans All right a travelling wave has a period of

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two seconds and amplitude of five millimeters and a wavelength

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of one meter What is its wave speed And here

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the pencil answers All right Okay well here we go

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So we're looking for the velocity of a wave here

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and no we're not talking about saying goodbye after a

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double espresso to find the velocity of a wave we

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multiply the wavelength times the frequency Uh but we don't

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know the frequency yet Minor detail let's strap on our

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math hat because they were about to figure it out

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And people we don't actually have a math hat It's

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more of a beanie rainbow beanie with a propeller Look

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it helps us think ok it's like they're googler All

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right Because frequency and period are reciprocal The equation to

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find the frequency is one over the period In this

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case the period is two seconds so the frequency is

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point five hurts right One over two in california is

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a half yet one too hard Now we can plug

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in the numbers remember way back when we mentioned at

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velocity equals wavelength times frequency Those were the days So

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the wavelength of one meter and a frequency of point

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five hearts our velocity is point five meters per second

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So the correct answer is b yeah we didn't use

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the amplitude even though it was given in the original

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question There's very good reason for that which is that

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it was irrelevant remember do not get hung up on

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using everything in a question just because a question gives

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us a quantity doesn't mean we have to use that

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to get the right answer Sometimes a test will try

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to throw us off our game by giving us too

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much information but our games too strong now for that

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to work on Now that we've reminded ourselves how strong

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we are we're going to go be brave and get

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back in the water on that surfboard We'll just start 00:02:02.1 --> [endTime] with a bathtub Yeah Baby steps people

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