"A man on the top of a tower, standing on the seashore, finds that a boat coming towards
Channel: Doubtnut
Date: 2020-04-05

"A man on
 the top of a tower, standing on the seashore, finds that a boat coming
 towards him takes 10 minutes for the angle of depression to change from `30o`
to `60o`
. Find the
 time taken by the boat to reach the shore from the position."