Question

A man fire a shoot and hear an echo after 2 sec he walk 85m towards the hill and again shoot he hear after 1.4sec . what is the velocity of sound and the distance between man and hill​

Answer 1

Given data,

T₁ = 2 sec

T₂ = 1.4 sec

V = ?

x = ?

D = 85m

Let

"x" be total distance between man and hill

"V" be velocity of sound

A) V = ?

As we know that,

Echo = 2d = v×t

   ⇒ V = 2d / t

   ⇒ V = (2×85) / (2-1.4)

   ⇒ V = 170/0.6

   ⇒ V = 283.3 m/s

B) X = ?

Distance is 2(x-340)

So  

V = 2(x-340)/3

since velocity of sound doesn't change

 ⇒ 2X/5=2(X-340)/3

⇒ X = 84.99 m

Hence,

V = 283.3 m/s

X = 84.99 m