Question

A boat, which has a speed of 5km/h in still water, crosses a river of width 1km along the shortest path possible in 20 minutes. Find the velocity of the river?

pls answer fast​

Answer 1

Answer:

ANSWER

Shortest possible path,s=1km

Time taken, t=15min=0.25hr

Speed in the direction of shortest path,

st = v 2 −u 2

Where, v=5kmh

−1velocity of boat, u velocity of river.

ts=

v 2 −u

2 0.251 = 5 2−u 2u=3kmh −1Hence, velocity of river is 3kmh −1