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A man can swim with a speed 4km/hr in st...

A man can swim with a speed 4km/hr in still water.
(a) How long does he takes to cross a river 1 km wide if the river flows steadily at 3 km/hr and makes his strokes normal to the river current?
(b) How far down the river does he go when he go when he reaches the other bank?

Text Solution

Verified by Experts

(a) time taken `t=(AB)/(v_(m))=(1)/(4)hr=15` min.
(b) The distance travelled along the river during its crossing is
`BC=v_(R)xxt=3xx(1)/(4)=0.75km`
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