The Bullet Block Experiment Everyone Gets WrongYouTube↗  IA↗(long shot)
Education  1.5M views 14.9K likes 494 dislikes   20 Aug 2013
Veritasium 20.8M subscribers United States YouTube↗


Please select the problem
You must specify your email and describe the problem in detail
Describe your problem in detail if it's not obvious

Contributed subtitles
Korean Bumgun Park
Thai Tee Ponsukcharoen
Click to Play Video Click to Play Video
Alright here is the setup: I have a rifle mounted vertically and we're going to shoot
여기 세팅해놓은게 있어요. 수직하게 설치해둔 소총이 있는데 이걸로 이 블록 한가운데에
a bullet into this block, right into the middle of it.
총알을 쏘아넣을거에요. 그럼 이 블록은 하늘을 향해서
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
날아오르겠죠. 이 실험을 더 할건데, 총알을 블록 정가운데에 쏘는게 아니라
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?
블록의 다른 부분에 쏴보려고해요. 어떻게 될지 예측해보세요. 우리가 다른 쪽에 쏜 회전하는 블록이 처음에 쐈던 블록이랑 같은 높이까지 날아갈까요? 더 낮을까요? 아니면 더 높이 갈까요?
Or will it go higher?
OK so versus being shot in the middle, when you shoot on the side is the question, right?
그래서 가운데에 쏘느냐 다른 한쪽에 쏘느냐가 문제인거죠?
Yeah. How high will it go in comparison?
- 그렇죠. 비교적으로 얼마나 올라갈 것인가인거죠. - 총알이 블록에 박혀있는 상태인거죠?
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.
- 그렇게 추정하는게 맞죠? - 블록에 박혀있습니다. 장담하죠.
Same height. I'm purely basing it on just like an instinct that I have.
같은 높이요. 그냥 순전히 본능적으로 느껴진대로 추정한거지만.
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
- 뭔가 속고 있는 기분이에요. - 왠지 지금 우리를 속이려고 하고
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
- 우리가 예측할 수 없는 그런 게 아닐까해요. - 제 생각에 명확한 답은 더 낮을 것 같으니까 - 더 높을 것 같다고 할게요. - 더 높이 갈 것 같아요. 대신에 - 다른 방향으로 날아가거나 하는 식일 것 같아요. - 그럼 각 모멘텀 L이 있을테고, - 병진 모멘텀 P가 있겠죠. - 블록 정가운데를 강타했을 때,
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.
그 블록은 회전하지 않고 어떤 특정한 높이까지 올라가겠죠.
But when you hit it on the side of the block, it's going to be spinning so it's going to
그런데 다른 부분을 강타하면, 블록이 회전하기 시작할테고 그로 인해
have imparted some kinetic energy so there won't be as much potential energy.
전달된 운동에너지가 생기겠죠. 그럼 위치에너지가 그만큼 생기진 않을거에요.
So the total energy of the system basically has to stay constant and the kinetic plus
계의 전체 에너지는 기본적으로 일정하기 때문에 운동에너지와 위치에너지의 합이
potential, which would be the height it goes to will have to be constant so if it's spinning
올라갈 높이가 되는데 에너지는 일정하겠죠. 그러니 블록이 회전하면
it has kinetic energy, it can't go as high. That's my prediction.
운동에너지가 필요할테고, 그만큼 올라가지 못하겠죠. 그게 제 예상 답안입니다.
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?
제 예상답안은 그만큼 높지는 않게 올라가지만 더 많이 회전할거라는겁니다. 틀렸나요?
I want you to think which do you think is the most reasonable and then click one of
저는 여러분들이 어떤 답이 가장 합리적인지 생각해보고 여기 있는 버튼을
the annotations above. Alright are you ready? Make your prediction in three, two, one...
클릭해주셨으면 해요. 준비되셨나요? 한번 예측해보세요. 3, 2, 1...
Similar videos:

Bullet Block Experiment Result
Veritasium
1.2M views 20.1K likes 368 dislikes 28 Nov 201375% match

Bullet Block Explained!
Veritasium
1.4M views 36.5K likes 636 dislikes 30 Aug 201335% match


Settings Privacy About Contact Donate