A boat man can row with a speed of 10 km/hr in still water. If the river flows at 5 km/h, the direction in which the boat man should row to reach a point on the other bank directly opposite to the point from where he started is (width of the river is 2km)

see full answer

High-Paying Jobs That Even AI Can’t Replace — Through JEE/NEET

🎯 Hear from the experts why preparing for JEE/NEET today sets you up for future-proof, high-income careers tomorrow.

An Intiative by Sri Chaitanya

In a direction inclined at $120^{0}$ to the direction of river flow

In a direction inclined at $90^{0}$ to the direction of river flow

$60^{0}$ in the North-West direction

Should row directly along the river flow

answer is A.

(Unlock A.I Detailed Solution for FREE)

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

$u \cos θ = \sqrt{u^{2} - v^{2}}$

$u^{2} \cos^{2} θ = u^{2} - v^{2}$

$100 \cos^{2} θ = 100 - 25 = 75$

$\cos^{2} θ = \frac{3}{4}$

$\cos θ = \frac{\sqrt{3}}{2} = \cos 30^{0}, θ = 30^{0}$

From the direction of river flow $= 30 + 90 = 120^{0}$

Watch 3-min video & get full concept clarity

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test