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Thank you We sneak And here's your smoke do as

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you are brought to you by horses Horses are beautiful

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majestic creatures And we make them carry us around it's

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Kind of like if we made george clooney give us

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a piggy back ride All right a printing press has

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two options for moving books A distance of forty meters

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The first option is a conveyor belt that runs for

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one hour on a single motor that provides a constant

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power of seventy five watts age a day The second

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option is a horse that pulls boxes of books with

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a constant force of one kilo newt by making ten

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one way trips The horse khun transport the same number

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of books is the conveyor belt In a single day

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the motor gets the job done in an hour by

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doing less work than the horse does in a day

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Well what's the difference in work done and here the

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pendulum killed Well boy we're dealing with some pretty ancient

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technology here Conveyor belts horse drawn wagons and books All

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right that's ok physics is timeless We've got this We

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know that work equals force times displacement but power in

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physics terms is work Divided by time we can rearrange

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that equation to find that work equals power times times

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that w p t we know that the conveyor belt

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motor runs for an hour and produces seventy five watts

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will use seconds as our unit of time And there

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are thirty six hundred seconds in an hour We'll when

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we plug in the numbers we see that the power

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produced by the conveyor belt is two hundred seventy Killer

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jules seven five three Now to figure out the work

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done by mr ed Remember him cold Ask your parents

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All right The horse produces a thousand newton's of force

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over the forty meter distance So the work done by

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the horse equals forty Kill a jewel But the horse

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makes this trip ten times So the total work done

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by the horse is for hundred killer jules Now we

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could just find a difference between the two So the

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correct answer is b if we ever have a horse

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when we better take good care of it and give

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it a character too is a tree Mr ed would

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be grumpy without character Well you know same thing goes 00:02:09.22 --> [endTime] for george but that's A different story

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