Question

A stone is dropped into a well. If the depth of water below the top be h and the velocity of sound is v, then the splash in water is heard after T second. Then

• A. $ T=\sqrt{\frac{2h}{g}}+\frac{h}{v} $
• B. $ T=2\sqrt{\frac{2h}{g}} $
• C. $ T=\frac{2h}{v} $
• D. $ T=\sqrt{\frac{2h}{g}}\times \frac{h}{v} $

Answer 1

Answer: (A)

Required time = time taken by stone to reach the water surface + time taken by sound to reach the top.
$ =\sqrt{\frac{2h}{g}}+\frac{\eta }{v} $