ShmoopTube

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And here's your shmoop du jour brought to you by superposition

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which of course is when Superman does yoga yeah like that..check out the [Superman doing yoga]

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following diagram....two waves of equal amplitude move [A diagram of waves on a laptop screen]

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toward each other with equal velocity when they reach each other which of the

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following can possibly occur? it's like two answers [pause button and car beeps]

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all right so what happens

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when two waves of run into each other along their travel do they crash into [two cars collide with each other]

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each other like cars and stop moving or do they keep on moving like nothing

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happened because well they're just that chill well the answer is all of the

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above they crash into each other and they also keep moving wait they crash [cars collide and continue moving in opposite directions]

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into each other and they keep moving yeah waves are weird like that they're

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kind of oblivious to the material world and just keep moving like us when we're [man studying while walking around a bedroom]

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studying for a big test like that remember that a wave travels through a

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medium but it doesn't transport it so when two waves collide matter isn't [waves colliding]

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colliding just energy is colliding the energy keeps on moving after the

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collision so answer A; not one of the right choices when waves do collide then

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we're dealing with superposition well superposition means that colliding waves

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will combine to make one single wave at the moment of collision the wave that [Two waves combine to form a single wave]

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results from the collision will equal the sum of the component waves and how

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the waves interact with each other is known as interference well interference [A wave in a phonebox and a phone outside of the phonebox]

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can be constructive or destructive kind of like criticism except less likely to

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make us cry/ Constructive interference occurs when waves of the same sign

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collide the amplitudes of the waves combine to form a larger amplitude like [Two positive waves collide forming a larger amplitude wave]

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that it's bigger and bigger destructive interference is what happens when a

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positive wave collides with a negative wave like flattens it out in this case

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the waves add up to have a smaller amplitude because they cancel each other

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out the ways have to have the same amplitude to cancel each other out [Waves cancel each other and flat line appears]

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completely so our correct answers are B and C either of these are

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possible, depending on whether the waves have the same sign or if they don't and

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we've seen that waves do interact so D is definitely not correct but after they [People with waves for bodies interacting in a street]

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meet the waves just keep on rolling, yeah waves are just zen like that and no

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Superman doesn't actually do yoga that's because the well the lotus position is

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his kryptonite.. Ow! [Superman in the lotus position]

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