Question

Elevation of a cloud is above the horizontal. A thunder is heard 8 second after the observation of the lightning. The speed of sound is 330 ms${}^{-1}$. The vertical height of the cloud from the ground is (sound reaches at an angle 60${}^o$ with horizontal)

• A. 8 x330m
• B. 8x 330 sin 60${}^o$m
• C. 8 x 330 cos 60${}^o$
• D. 8 x 330 tan 60${}^o$m

Answer 1

The correct option is B 8x 330 sin 60${}^o$m

Distance $=\vartheta \times t$

So, $\frac{h}{sin{60}^0}=\vartheta \times t$

$h=\vartheta \times t\times sin{60}^{0}m$ $=330\times 8\times sin{60}^{0}m$