字幕表 動画を再生する 英語字幕をプリント 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...