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Most Important Selected Qs for JEE AdvancedPhysicsMotion in One Dimension

A swimmer can swim in still water with a speed of 5 ~m / s . While crossing a river his average speed is 3 ~m / s . If he cross the river in the shortest possible time, what is the speed of flow of water?

Options

  1. A2 ~m / s
  2. B4 ~m / s
  3. C6 ~m / s
  4. D8 ~m / s

Correct answer

A. 2 ~m / s

Step-by-step solution

Avg. speed 3= (v_ r t )^2+ ( v _ mr t )^2 t aligned & v_r^2+5=9 & v_r=2 ~m / s aligned

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