Question

the splash is heard after 4.22 sec after the stone is dropped into a well of depth 78.4 the velocity of sound is

Answer 1

let stone take time t to reach to bottom

-78.4=0*t-1/2(g)t*t
t=4
time taken by sound is=4.22-4=0.22s

velocity of sound is = 7.4/0.22=356.36 m/s

Answer 2

78.4=0*t-1/2(g)t*t

t=4

time taken by sound is=4.22 - 4 = 0.22 s

velocity of sound is = 7.4/0.22 = 356.36 m/s