I'm interested in the case of cliff jumping. It is dangerous because if you are jumping from a height the water resistance will stop you like concrete. However, you mitigate this by jumping in a streamlined position, including pointed toes, locked knees, arms straight vertical, etc.

But I am curious that if you are going to be killed by hitting the bottom at a high speed, even if you survived the initial impact. For example, I hit the bottom of a 3.7-metre deep pool fast even I just walked into it at the edge of the pool. Let's assume the following dimension:

  1. The jump is done vertically in the most streamlined way possible.
  2. The jumping man has a neutral buoyancy on the surface of water.
  3. The jumping man keeps the streamlined position even after entering the water, until the deceleration due to water resistance stops.

If the man jumps from x m height, how I can calculate

  1. The terminal speed after entering water.
  2. How deep in water he will attain the terminal speed.

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