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An open vessel completely full of water is in free fall under gravity. There is a small hole in one side wall of the vessel. At the instant the hole is at height H above the ground, what happens to the water emerging from the hole and where does it land relative to point P directly below?

1. The value of x is 2*sqrt(2*h*H/3)
2. The value of x is sqrt(4*h*H/3)
3. The value of x cannot be computed from the information provided.
4. No water comes out from the hole.

Correct answer: No water comes out from the hole.

Solution

During free fall both the vessel and the water accelerate downward at g, so the water is weightless relative to the vessel. The hydrostatic pressure that normally drives water out becomes zero, so there is no efflux velocity and no water comes out of the hole.

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