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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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