Plunging into water feet first, as streamlined as you can be

AI Thread Summary
The discussion focuses on the dynamics of plunging into water feet first and the calculations involved in determining the impact force. It emphasizes the importance of body positioning for maximizing streamline during the plunge. While exact calculations of forces over time are complex, an estimate can be made by considering the displacement of water equal to the body's volume. The conversation also questions whether the rate of change of volume (dV/dt) can provide insights into the impact force experienced upon hitting the water. Understanding these factors is crucial for assessing the safety of such jumps.
siddharth23
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There is a thread on plunging into water but it doesn't specify how you land. Consider that a man plunges into the water vertically with his toes pointing downwards, streamlining his body to the maximum possible extent. How can you calculate if the person falling will die or not? Rather how can you calculate the force he will be subjected to when he hits the water?
 
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There are a few old threads on that question. An exact calculation of the forces over time is very difficult, but you can get a pretty decent estimate just by considering that in the time between first touching the water and being completely submerged, a volume of water equal to the volume of the body must be displaced.
 
Right. Got that part. But will dV/dt give an idea of the force?
 
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