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The river 500 m wide is flowing with a c...

The river 500 m wide is flowing with a current of 4kph. A boat starts from one bank of the river wishes to cross the river at right angle to stream direction. Boatman can row the boat at 8 kph. In which direction he should row the boat. What time he ''ll take to cross the river ?

Text Solution

Verified by Experts

The correct Answer is:
`44-33`
`8 sin theta =4`
`v_(y)=8 cos theta`
`sin theta =1/2= 8 xx(1.73)/(2)`
time taken `=(1//2)/(4xx1.73)` hours 4.33 min
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[" 16.Water is flowing in a river of width "36m" with a speed of "2ms^(-1)" .A person in a boat "],[" at a point "p" on the bank of the river wants to cross the river by the shortest path to "],[" reach a point "Q" directly opposite on the other bank.If he can row his boat with a "],[" speed of "4ms^(-1)" in still water,he should row his boat at an angle of (multiples of "],[10^(@)" ) "]