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A battalion of soldiers is ordered to sw...

A battalion of soldiers is ordered to swim across a river `500 m` wide. At what minimum rate should they swim perpendicular to river flow in order to avoid being washed away by the waterfall 300 m downstream. The speed of current being 3m/sec:

A

`10 m//s`

B

`5 m//s`

C

`4 m//s`

D

`3 m//s`

Text Solution

Verified by Experts

The correct Answer is:
B

`t=(300)/(3)=100 sec`.
`v=(500)/(t) =5 m//s`
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