A BOAT WHICH HAS A SPEED IS 5 Km/Hr IN STILL WATER CROSSES A RIVER OF WIDTH 1 Km along the shortest possible path in 15 minutes. find velocity of the river water.

Answer 1

its average speed across is 4km/hr.

draw the diagram.

using the pyth theorem,

5^2=vs^2+4^2

looks like the velocity of the stream is 3Km/hr

Answer 2

Vbw = 1km/15Min = 1km/0.25h = 4km/h =
Velocity of boat with respect to the water.

Vbw = Vb + Vw = 4i
5i + Vw = 4i
Vw = -1i = 1km/h[-90o] = 1km/h Due South