Discussion Forum



1)

A person swims in a river aiming to reach exactly on the opposite point on the bank of a river His speed of swimming is 0.5 m/s at an angle of 120° with the direction of flow of water. The speed of water is


A) 1.0m/s

B) 0.5m/s

C) 0.25m/s

D) 0.43m/s

Answer:

Option C

Explanation:

Let the speed of water = $\overline{u}$

Speed of swimmer = $\overline{v}$ = 0.5m/sec

Angle between $\overline{u}$ and $\overline{v}$ is 120°. Then

$\sin\theta=\frac{\overline{u}}{\overline{v}}$ = $\frac{u}{0.5}=\frac{1}{2}$ or u=0.25ms-1

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