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A stone is released from rest into a well, and the water surface lies at a depth h below the top. If the speed of sound is v, the total time after release at which the splash is heard is

1. T = 2h/v
2. T = √(2h/g) + h/v
3. T = √(2h/v) + h/g
4. T = √(h/2g) + 2h/v

Correct answer: T = √(2h/g) + h/v

Solution

The correct option accounts for two phases: the time it takes for the stone to fall to the water surface, which is determined by the equation of motion under gravity, and the time for the sound to travel back up to the top of the well, which is based on the speed of sound. Thus, the total time is the sum of these two components.

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