Question

a stone is dropped from the top of the tower 125 m high into the pond of water at the base of the tower. when is the splash heard at the top ? (g= 10 m/s square and speed of sound = 342m/s)

Answer 1

this question has to be solved in two parts first time taken by stone to reach the surface of water in pond and the time taken by the sound waves to reach the height after being produced
so
s=ut +1/2gt1^2
-125=1/2 x -10 x t1^2
125=5t1^2
t1^2=25 t=5

now time taken by sound waves to come to height
s=vt
125=342 x t2
t2=.36 sec
so
t1 + t2 = 5.36