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Alright here is the setup: I have a rifle mounted vertically and we're going to shoot
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a bullet into this block, right into the middle of it.
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So obviously the block is going to go flying into the air.
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But we're going to do this again and instead of firing the bullet right into the middle
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of the block, we're going to shoot it off to one side and I want you to make a prediction.
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Will that spinning block, when we shoot hit it to one side, will it go the same height
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as this first block?
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Will it go not as high?
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Or will it go higher?
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OK so versus being shot in the middle, when you shoot on the side is the question, right?
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Yeah.
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How high will it go in comparison?
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It depends on if the bullet stays in the block - and I'm assuming it does?
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It does stay in the block, yes, I'll guarantee you that.
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Same height.
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I'm purely basing it on just like an instinct that I have.
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I feel like I'm being tricked.
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I just feel like you're trying to trick us and that it's going to do something that we
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can't predict.
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I feel like the obvious answer is not as high so I'm going to say higher.
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I'll say higher, but it's going to like fly in a different direction or something.
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So you have angular momentum, which is L, and you have translational momentum, which
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is P. When you hit it in the middle of the block, the block doesn't really spin at all
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so it just goes up to a certain height.
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But when you hit it on the side of the block, it's going to be spinning so it's going to
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have imparted some kinetic energy so there won't be as much potential energy.
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So the total energy of the system basically has to stay constant and the kinetic plus
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potential, which would be the height it goes to will have to be constant so if it's spinning
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it has kinetic energy, it can't go as high.
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That's my prediction.
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So my prediction is it'll go up, not as high but it'll spin more if it's hit to the side.
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Am I wrong?
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I want you to think which do you think is the most reasonable and then click one of
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the annotations above.
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Alright are you ready?
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Make your prediction in three, two, one...
