Question

a stone is dropped from roof of building takes 5 seconds to reach the ground the sound of striking is heard after 5.4 second of the stone is dropped the velocity of sound is

Answer 1

u=0,a=-10,t=5(in stone's downward journey)
[S=ut+1/2at^2]=putting values we get (S=125)
bcus air friction is not consider
so,
for sound we easily put
Speed=Distance/Time
as whole time=5.4
so in upward journey of sound the time taken is=.4sec
so by solving:
Velocity of sound=125/.4
we get,
ANSWER=312.5