A man wishes to swim across a river 0.5 m wide. If he can swim at the rate of 2 Km/ h in still water and the river flows at the rate of 1 km/hr. The angle (wrt flow of water) along which he should swim so as to reach a point exactly opposite his starting point, should be?

Question

abhisar · Answer

@Michele_Laino

abhisar · Answer

@JoannaBlackwelder

vincent-lyon.fr · Answer

Hint: Draw a picture in order to add up the velocities.

michele_laino · Answer

the velocity of the swimmer with respect to the water is 2 Km/hour, whereas the velocity of the current is 1 Km/hour, so the situation of your problem is like in my drawing:
|dw:1437510950238:dw|

michele_laino · Answer

Now, I stay on the bank of the river and I use my stopwatch to measure the time needed to the swimmer to cross the river. within that time the swimmer travels the distance AB:
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