Question

A man stands in between two cliffs, such that he is at a distance of 133.6 m from the nearer cliff. He fires a gun and hears the first echo after 0.8 s and the second echo after 1.8 s. Calculate : (a) speed of sound (b) distance between the two cliffs.

Answer 1

(a) Speed of sound \[ v = \frac{2d}{t} \]

\[ = \frac{2 \times 133.6}{0.8} \]

= 334 ms⁻¹

(b) Distance of the man from the farther cliff \[ d_2 = \frac{v \times t}{2} \]

\[ = \frac{334 \times 1.8}{2} \]

= 300.6 m

Distance between the two cliffs = d₁ + d₂

= (133.6 + 300.6)

= 434.2 m