91
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:
Answer & Solution
Answer: Option
A
Solution:


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








