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

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Brought to you by spinning plates Watching people spin plates

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actually is to be a popular form of entertainment Don't

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ask us what Alright check out following diagram this thing

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spinning plate right there A glass plate of mass and

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radius are there is spinning on top of a pole

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has shown all right Which of the following would increase

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the rate at which the plates spin Select two here

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in the aisle All right well let's see we're dealing

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with something That's turning huh That must mean we're dealing

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with angular momenta ding ding because we're geniuses We know

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that angular momentum equals mass times velocity times the objects

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radius or we just got a clever too one day

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And because we're super geniuses we know that momentum is

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conserved whether that's angular momentum or linear momentum So once

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forces applied and objects total momentum won't change unless another

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force acts on it So if momentum doesn't change we

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know that if we want to raise velocity we have

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tto lower one of the other variables That means we

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can decrease the mass of the plate or decrease the

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radius of the plate We'll do it Either it is

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or both would mean that the velocity would have to

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increase to maintain a total angular momenta So are correct

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choices are a and c and looking at our equation

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we can see that the length of the pool doesn't

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affect angular momentum so be doesn't work and placing a

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small way that the edge of the plate would increase

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mass was it would throw off the delicate balance of

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the plate and well ruin the whole act You don't

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even wanna think about Answer date Speaking of super genius

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is conservation of momentum is another of isaac newton's contributions

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to physics It comes from his laws of motion but

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he wasn't much of a place better He wouldn't All 00:01:43.663 --> [endTime] my great no

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