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A person reaches on a point directly opp...

A person reaches on a point directly opposite on the other bank of a river.The velocity of the water in the river is `4 m//s`and the velocity of the person in still water is `5 m//s`.If the width of the river is `84.6m`, time taken to cross the river in seconds is

A

9.4

B

2

C

84.6

D

28.2

Text Solution

Verified by Experts

The correct Answer is:
D
`t=d/sqrt(v_(b)^(2)-v_(w)^(2))`
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Knowledge Check

  • A person, reaches a point directly opposite on the other bank of a flowing river, while swimming at a speed of 5 m/s at an angle of 120^(@) with the flow. The speed of the flow must be

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    2.5 m/s
    B
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    C
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    D
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  • A swimmer wishes to reach directly opposite bank of a river, flowing with velocity 8 m/s. The swimmer can swim 10 m/s still water. The width of the river is 480 m. Time taken by him to do so:

    A
    60 sec
    B
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    C
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    D
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  • A man can swim in still water at a speed of 6 kmph and he has to cross the river and reach just opposite point on the other bank.If the river is flowing at a speed of 3 kmph ,and the width of the river is 2km , the time taken to cross the river is (in hours)

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