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

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Brought to you by skate parks there's all sorts of

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physics going on at these places mostly the gravitational kind

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of physics course All right The whole skate park is

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watching maria's under pressure and really needs to nail this

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trick Well she sets off build speed and grinds the

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board down a pair of railings Well she makes perfect

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landing in turns to face the cheers Her boards Mel

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bar has a width of d and slides with the

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velocity v across the smooth metal rails All right this

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event occurs under a uniform magnetic field Be directed into

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the page The end of the railing has a resistance

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Are the sliding rod creates emotional e m f mathematically

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expressed as or epsilon equals B devi right Which of

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the following changes will increase the power dissipated by the

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resistor select two answers And here our options decreases and

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increases There we go Well good for maria We tried

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skateboarding for awhile It didn't go quite as well It

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will stick to physic for now And well there's Last

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chance injuries figure out the power dissipated by the resister

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we need to use The right equation that is power

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equals current times voltage And it also equals current squared

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times Resistance Well right off the bat Looking at this

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we can see that decreasing the current won't increase the

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power So answer a isn't one of the right choices

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but let's look at the current in terms of owns

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law Oh does that get according to our body current

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equals electoral motive force over resistance and we know that

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the m f equals magnetic field times distance times velocity

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But we can swap that equation for the imf to

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get a new equation for current Well now we can

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go back to our power equation and put it all

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together Power equals the imf equation squared over the resistance

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squared times resistance Well when we simplify all that we

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see that power equals b d v squared over r

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which means that increasing velocity or distance will increase the

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power dissipated The answer is b and c or the

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right choices Now we just need to give skateboarding another

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shot If you fall off the horse you're supposed to 00:02:23.99 --> [endTime] just get right back on right

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