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The speed of a boat is 5 km/h in still-w...

The speed of a boat is 5 km/h in still-water. It crosses a river of width 1 km along the shortest path in 20 min. The velocity of river water in km/h is

A

5

B

1

C

3

D

4

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The correct Answer is:
D
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BINA LIBRARY-KINEMATICS - 1-EXERCISE
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  2. Speeds of two identical cars are v and 4v at a specific instant. The r...

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  3. The speed of a boat is 5 km/h in still-water. It crosses a river of wi...

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  4. Thief's car is moving with a speed of 10m/s. A police van chasing the ...

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  5. A particle is moving with a velocity 5m/s towards east and its velocit...

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  6. A body falling from a height travels 40 m in the last 2s of its fall t...

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  7. A stone dropped into a lake form a tower 500 m high. The sound of spla...

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  8. The velocity of a body depends on time according to v = 20 + 0.1t^2 . ...

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  9. If X = at + bt^2 , where X is distance travelled by a body in km while...

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  10. The equation sqrtx = t+9 gives the variation of displacement with time...

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  11. A body starts from rest. The ratio of the distances travelled by it du...

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  12. A body is released from a height and falls freely. Another body is rel...

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  13. A body dropped from a height h with an initial speed zero reaches the ...

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  14. Water drops fall at regular intervals from a tap, which is 5 m above t...

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  15. A train 150 m in length is moving north at a speed of 10m/s. A parrot ...

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  16. For a body moving along a straight line, the average velocity is equal...

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  17. If the time-displacement graph of a particle is parallel to time-axis,...

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  18. When a particle is moving with uniform velocity which of the following...

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  19. The distance covered by a body moving along a straight line is proport...

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  20. If a body starts from rest and travels 1.2 m in 8th second , then acce...

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