ShmoopTube

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Thank you We sneak and here's your shmoop du jour

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brought to you by impulse To be clear we're talking

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about impulse in physics not about that sweater We shouldn't

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have bought a wooden block and a rubber wall collide

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which of the following quantities would need to be known

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in order to calculate the impulse of the collision It's

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like two answers right near the options All right well

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in physics impulses the transfer of mo mentum from one

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object to another Think of a game of pool when

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we strike the cue ball with the stick there's a

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transfer of mo mentum like here to here when the

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cue ball strikes another ball well that's another transfer of

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mo mentum each collision is an impulse where the force

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of one object delivers momentum to another object over a

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given period of time Impulses defined his force times the

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change in time equation looks like this because we're good

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physics students way know that force equals mass times acceleration

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right We just know that And since we're great physics

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students problem we know that acceleration equals velocity divided by

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time Write a will overtake Now the force equation can

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live like this force equals mass times the quotient of

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velocity divided by time And while we're having fun with

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equations that means that if we multiply both sides by

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time we'll see that force times time equals mass times

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velocity In other words the impulse of force times time

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equals mo mentum and that means we don't need to

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know the coefficient of friction of the surface The block

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is sliding on and we also don't need to know

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the kinetic energy of the block The options being dear

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incorrect to things We need no r a the mass

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of the block and see the change in its velocity

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That's it way also need to know if the place

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were bought This sweater from takes returns because this thing's 00:01:54.516 --> [endTime] just titties

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