Question

A boat which has a speed of 5 kilometre per hour in stillwater crosses a river of width 1km along the shortest possible path in 15 minutes. what is the velocity of the river water

Answer 1

Given -

v=5km/hr

S=1km t=15/60 hr.


From second eq . Of motion

1=1/2×a×(15/60)^2a=8m/s^2

From first eq . Of motion

5= u+8×15/60

Hence.

u=3km/hr

hop it will help you..

Answer 2

Answer:

The velocity of river stream is 3 km/hr.

Explanation:

The speed of the boat along the shortest possible path

$AB = \frac{1}{\frac{15}{16} } = 4 km/hr$

Now, The velocity of river water

$V = \sqrt{5^{2}-4^{2} } = \sqrt{25-16} = \sqrt{9} = 3 km/hr$