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A river is flowing from east to west at ...

A river is flowing from east to west at a speed of 5m/min. A man on south bank of river, capable of swimming 10m/min in still water, wants to swim across the river in shortest time, he should swim:-

A

Due north

B

Due north-east

C

Due north-east with double the speed of river

D

None of the above

Text Solution

Verified by Experts

The correct Answer is:
A
For shortest time then maximum velocity is in the direction of displacement.
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ALLEN -KINEMATICS-EXERCISE-01
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  2. A boat which has a speed of 5km per hour in still water crosses a rive...

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  3. A river is flowing from east to west at a speed of 5m/min. A man on so...

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  4. Two particles P and Q are moving with velocity of (hat(i)+hat(j)) and ...

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  5. From a motorboat moving downstream with a velocity 2 m//s with respect...

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  6. A small ball is projected up a smooth inclined plane with an initial s...

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  7. Graph I and II give coordinates x(t) and y(t) of a particle moving in ...

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  8. Particle is dropped from the height of 20 m from horizontal ground. A ...

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  9. The total speed of a projectile at its greater height is sqrt(6/7) of ...

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  10. A projectill is projected at an angle (alpha gt 45^(@)) with an initia...

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  11. A particle is projected from a horizontal plane (x -z plane) such that...

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  12. A particle is dropped from a height H.The de-Broglie wavelength of the...

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  13. A particle is projected from a tower as shown in figure, then find the...

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  14. In the fig., the ends P and Q of an unstrechable string move downwards...

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  15. A block is dragged on a smooth plane with the help of a rope which mov...

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  16. A weightless inextensible rope rest on a stationary wedge forming an a...

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  17. If acceleration of M is a then acceleration of m is

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  18. If accelration of A is 2m//s^(2) towards left and accleration of B is ...

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  19. If angular velocity of a disc depends an angle rotated theta as omega=...

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  20. If the radii of circular path of two particles are in the ratio of 1 :...

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