A Man Wants To Reach Point B On The Opposite Bank Of A River Flowing At A Speed. What Minimum Speed Relative To Water Should The Man Have So That He Can Reach Point B. In Which Direction Should He Swim?

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Question

A man wants to reach point B on the opposite bank of a river flowing at a speed. What minimum speed relative to water should the man have so that he can reach point B. In which direction should he swim?

Solution

Correct option is

 

Let v be the speed of boatman in still water.

Resultant of v and u should be along AB. Components of  along x and y direction are.

          

          

v is minimum at

          

               .

 

SIMILAR QUESTIONS

Q1

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Q2

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Q3

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