As observed from the top a light house, 120√3 m above the sea level, the angle of depression of a ship sailing towards it changes from 30° to 60°. The distance travelled by the during the period of observation is:

A. 240 m

B. 240√3 m

C. 180√3 m

D. 180 m

Answer: Option A

Solution(By Examveda Team)

$$\eqalign{ & \sqrt 3 \to 120\sqrt 3 \cr & 1{\text{u}} \to 120 \cr & 2{\text{u}} \to 120 \times 2 = 240{\text{m}} \cr} $$