Question

A swimmer crosses a flowing stream of width ω to and fro in time t₁ .The time taken to cover the same distance up and down the stream is t₂ . If t₃ is the time the swimmer would take to swim a distance 2ω in still water, then

[a] t₁²= t₂t₃

[b] t₂=t₃

[c] t₃²=t₂t₃

[d] t₃=t₁ + t₂

Answer 1

The correct option is (a) t₁² = t₂t₃

Explanation:

Suppose velocity of swimmer in still water = u

Velocity of swimmer in river water = v

Then,

Comments

how t1 = 2* tcrossing came ?