question is in the description

Question

A rock dropped into a pond sends out a circular ripple whose radius increases steadily at 6cm/s. A toy boat is floating on the pond 2m east and 1 m north of the spot where the rock is dropped. How long does it take for the ripple to reach the boat

Answer 1

Find the distance from the point where the rock is dropped, to the boat.  Divide that distance by the speed of the ripple, and that is the time required for the ripple to reach the boat.

 

d = √(2² + 1²) m = √5 m.

 

t = d/v = (√5 m)/(0.06 m/s) ≅ 37.3 s