Question

a man fires a gun and hears its echo after 5sec .the man moves 310m towards the hill and fires again.if hears the echo after 3sec ,show the sum by calculating the speed of sound​

Answer 1

Let Distance be equal to 'x'

Then the total distance to travel

= 2x

Time = 5s

Speed = Distance/Time

Speed = 2x/5. eq.1

2nd situation

Distance = x - 310

Total distance = 2(x-310)

= 2x - 620

Time = 3 sec

Speed = (2x - 620)/3. eq.2

From eq.1 and eq.2

2x/5 = (2x-620)/3

6x = 5(2x - 620)

6x = 10x - 3100

4x = 3100

x = 3100/4 = 775

775m is the distance

Speed = 2x/5. from eq.1

= 2(775)/5

= 1550/5

= 310m/s

Answer 2

This is answer mate. If it helps you