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A river of width d is flowing with a vel...


A river of width d is flowing with a velocity u. A person starts from point A. He always try to keep himself along y axis. Speed of man w.r.t to river at any position is given by `v=ksqrt(y)(kto+ve` constant). Time taken by man to cross the river is (Assume that at t=0,y=0)

A

`sqrt((d)/(k))`

B

`2sqrt((d)/(k))`

C

`(2sqrt(d))/(k)`

D

`(2d)/(sqrt(k))`

Text Solution

Verified by Experts

The correct Answer is:
C
`t=int(dy)/(V_(y))=underset(0)overset(d)int(dy)/(Ky^(1//2))=(2sqrt(d))/(k)`
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