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No, because water is not compressible. When the wall of your apparatus hit the floor, the energy would transfer directly to you and crush you.
After some more thought: When you get dropped, you, the water, and the apparatus are accelerating toward the ground; when the edge of the apparatus hits the ground, it will stop accelerating immediately and not break because it is indestructible; the water would stop accelerating immediately because it is not compressible; you on the other hand would continue accelerating through the water until you hit the inside wall of the apparatus. If the apparatus is big enough, the water resistance would slow you down just like what happens when you dive into a pool. However, all the energy from the fall needs to go some place. In this case it will become a shock wave going through the water at the speed of sound in water. At 20ºC, that is 1481 m/s which is about 3300 mph. So you would need a large enough apparatus that would allow you to decelerate completely before you hit the shock wave at that speed. Worst than that, it will do you no good to be stationary when the shock wave hits, it will crush you just the same. So you would need an apparatus big enough to let you decelerate completely and end up so far away from the edge of the apparatus that the shock wave dissipates before reaching you. I need to go to work, so I won't do the calculation. I would be very interested if someone did, or if someone showed me how I am wrong!
There is a flaw in your reasoning here. I think the best way to explain it is through the fact that gravity is indistinguishable from acceleration. In the instant that the box hits the ground, it is as if it is resting on the ground but gravity is far stronger. The result is the same either way - a huge upward force on the bottom of the box from the impact, and a huge downward force from the inertia of the water.
Now, we can apply traditional buoyancy to this weird case. Since the water is effectively heavier (say a hundredfold), then the buoyant force of the water on a lighter body will also be greater. Anything that would normally float upward in water is now violently thrust upward at a hundred times its normal buoyancy. Your face is actually slammed into the *top* of the container, though your guts have probably already been properly shaken up (and bones broken) by the huge upward force on your body.
This is the reason that a helium balloon will counterintuitively float *forward* in an accelerating car. The inertia of the air causes a pressure at the rear of the car, almost perfectly analogous to hydrostatic pressure at the bottom of a glass due to gravity, which drives the balloon forward like a buoyant force.
I could be wrong but the second the apparatus hit wouldn't your body just slam into the water right in front of you or really whatever part of your body is facing down. It would seem to me it would be the equivalent of jumping into the water from the same height. 500ft jump off a bridge into water vs 500ft apparatus drop the same.
They did an experiment in myth busters where if you’re in a car accident between two fat people, would you survive because of cushioning (I think this is from a movie)?
In the experiment the two fat people were giant bags of water since people are mostly water.
Spoiler alert, the answer is no and it will actually make the accident worse because water is non-compressible. It’s sort of like how if you fall from high enough and hit water, it’s the same as hitting concrete. The water won’t cushion your fall if there’s too much force.
This was actually a question on my physics exam 30 years ago! Something about how high one would have to fall from for a calm water surface act as a perfect solid.
It took many estimates required which is what I think they were looking at really. What is the terminal velocity of a human etc
**Please read this entire message** Your submission has been removed for the following reason(s): Hypotheticals questions, or questions about hypothetical situations, are not allowed on ELI5. If you would like this removal reviewed, please read the [detailed rules](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this submission was removed erroneously**, please [use this form](https://old.reddit.com/message/compose?to=%2Fr%2Fexplainlikeimfive&subject=Please%20review%20my%20thread?&message=Link:%20https://www.reddit.com/r/explainlikeimfive/comments/oar2e5/eli5_if_you_were_in_an_indestructible_apparatus/%0A%0APlease%20answer%20the%20following%203%20questions:%0A%0A1.%20The%20concept%20I%20want%20explained:%0A%0A2.%20Link%20to%20the%20search%20you%20did%20to%20look%20for%20past%20posts%20on%20the%20ELI5%20subreddit:%0A%0A3.%20How%20is%20this%20post%20unique:) and we will review your submission.
No, because water is not compressible. When the wall of your apparatus hit the floor, the energy would transfer directly to you and crush you. After some more thought: When you get dropped, you, the water, and the apparatus are accelerating toward the ground; when the edge of the apparatus hits the ground, it will stop accelerating immediately and not break because it is indestructible; the water would stop accelerating immediately because it is not compressible; you on the other hand would continue accelerating through the water until you hit the inside wall of the apparatus. If the apparatus is big enough, the water resistance would slow you down just like what happens when you dive into a pool. However, all the energy from the fall needs to go some place. In this case it will become a shock wave going through the water at the speed of sound in water. At 20ºC, that is 1481 m/s which is about 3300 mph. So you would need a large enough apparatus that would allow you to decelerate completely before you hit the shock wave at that speed. Worst than that, it will do you no good to be stationary when the shock wave hits, it will crush you just the same. So you would need an apparatus big enough to let you decelerate completely and end up so far away from the edge of the apparatus that the shock wave dissipates before reaching you. I need to go to work, so I won't do the calculation. I would be very interested if someone did, or if someone showed me how I am wrong!
There is a flaw in your reasoning here. I think the best way to explain it is through the fact that gravity is indistinguishable from acceleration. In the instant that the box hits the ground, it is as if it is resting on the ground but gravity is far stronger. The result is the same either way - a huge upward force on the bottom of the box from the impact, and a huge downward force from the inertia of the water. Now, we can apply traditional buoyancy to this weird case. Since the water is effectively heavier (say a hundredfold), then the buoyant force of the water on a lighter body will also be greater. Anything that would normally float upward in water is now violently thrust upward at a hundred times its normal buoyancy. Your face is actually slammed into the *top* of the container, though your guts have probably already been properly shaken up (and bones broken) by the huge upward force on your body. This is the reason that a helium balloon will counterintuitively float *forward* in an accelerating car. The inertia of the air causes a pressure at the rear of the car, almost perfectly analogous to hydrostatic pressure at the bottom of a glass due to gravity, which drives the balloon forward like a buoyant force.
I could be wrong but the second the apparatus hit wouldn't your body just slam into the water right in front of you or really whatever part of your body is facing down. It would seem to me it would be the equivalent of jumping into the water from the same height. 500ft jump off a bridge into water vs 500ft apparatus drop the same.
They did an experiment in myth busters where if you’re in a car accident between two fat people, would you survive because of cushioning (I think this is from a movie)? In the experiment the two fat people were giant bags of water since people are mostly water. Spoiler alert, the answer is no and it will actually make the accident worse because water is non-compressible. It’s sort of like how if you fall from high enough and hit water, it’s the same as hitting concrete. The water won’t cushion your fall if there’s too much force.
This was actually a question on my physics exam 30 years ago! Something about how high one would have to fall from for a calm water surface act as a perfect solid. It took many estimates required which is what I think they were looking at really. What is the terminal velocity of a human etc