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  • Alright here is the setup: I have a rifle mounted vertically and we're going to shoot

  • a bullet into this block, right into the middle of it.

  • So obviously the block is going to go flying into the air.

  • But we're going to do this again and instead of firing the bullet right into the middle

  • of the block, we're going to shoot it off to one side and I want you to make a prediction.

  • Will that spinning block, when we shoot hit it to one side, will it go the same height

  • as this first block?

  • Will it go not as high?

  • Or will it go higher?

  • OK so versus being shot in the middle, when you shoot on the side is the question, right?

  • Yeah.

  • How high will it go in comparison?

  • It depends on if the bullet stays in the block - and I'm assuming it does?

  • It does stay in the block, yes, I'll guarantee you that.

  • Same height.

  • I'm purely basing it on just like an instinct that I have.

  • I feel like I'm being tricked.

  • I just feel like you're trying to trick us and that it's going to do something that we

  • can't predict.

  • I feel like the obvious answer is not as high so I'm going to say higher.

  • I'll say higher, but it's going to like fly in a different direction or something.

  • So you have angular momentum, which is L, and you have translational momentum, which

  • is P. When you hit it in the middle of the block, the block doesn't really spin at all

  • so it just goes up to a certain height.

  • But when you hit it on the side of the block, it's going to be spinning so it's going to

  • have imparted some kinetic energy so there won't be as much potential energy.

  • So the total energy of the system basically has to stay constant and the kinetic plus

  • potential, which would be the height it goes to will have to be constant so if it's spinning

  • it has kinetic energy, it can't go as high.

  • That's my prediction.

  • So my prediction is it'll go up, not as high but it'll spin more if it's hit to the side.

  • Am I wrong?

  • I want you to think which do you think is the most reasonable and then click one of

  • the annotations above.

  • Alright are you ready?

  • Make your prediction in three, two, one...

Alright here is the setup: I have a rifle mounted vertically and we're going to shoot

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A2 block prediction bullet kinetic height shoot

Bullet Block Experiment

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    林宜悉 posted on 2020/03/28
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