A stone is dropped into a lake from a tower 500 m high. The sound of the splash will be heard by a man on the tower after: [Assume speed of sound .=330 m / s ; g =10 m / s 2]

Question

A stone is dropped into a lake from a tower 500 m high. The sound of the splash will be heard by a man on the tower after: [Assume speed of sound .=330 m / s ; g =10 m / s 2] (A) 10 s (B) 11.5 s (C) 14 s (D) 21 s

Tardigrade Admin · Accepted Answer

As (1/2)gt2 = ∴ t = √(2S/g) = √(2 × 500/10) = 10 s Time taken by sound = (500/350) = 1.5 s Total time = 10 + 1.5 = 11.5 s

Q. A stone is dropped into a lake from a tower $500 m$ high. The sound of the splash will be heard by a man on the tower after:
[Assume speed of sound $= 330 m / s; g = 10 m / s^{2}]$

10 s

11.5 s

14 s

21 s

As $\frac{1}{2} g t^{2}$ = $∴$ t = $\frac{2 S}{g} = \frac{2 \times 500}{10}$ = 10 s
Time taken by sound = $\frac{500}{350}$ = 1.5 s
Total time = 10 + 1.5 = 11.5 s

Q. A stone is dropped into a lake from a tower 500m high. The sound of the splash will be heard by a man on the tower after: [Assume speed of sound =330m/s;g=10m/s2]