Question

a man fires the gun and hears its echo after 5 seconds then the man moves 310 metre towards the hill amd fires the gun again this time he hears the Echo after 3 seconds calculate the speed of sound. plz solve it completely.

Answer 1

V = 2d/t [formula]

Solution :

V = 2 X 310/2 [when he moves 310m towards the cliff he hears the echo                                 after 3s. So  5 - 3 = 2s ]
V = 310m/s

Total distance from the cliff :

      V = 2d/t
  310 = 2d/5
1550 = 2d [cross multiplication]
  755 = d

Final answer : 755m

                                       Hope it helps................