A Man Can Swim At A Speed Of 3 Km/hr In Still Water. He Wants To Cross A 500 M Wide River Flowing At 2 Km/hr. He Keeps Himself Always At Angle Of 120o With The River Flow When Swimming Find The Time He Takes To Cross The River.

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A man can swim at a speed of 3 km/hr in still water. He wants to cross a 500 m wide river flowing at 2 km/hr. He keeps himself always at angle of 120o with the river flow when swimming find the time he takes to cross the river.


Correct option is


             Vr1g = velocity of the river with respect to the ground

           Vm1r = velocity of the man with respect to the river

          Vm1g = velocity of the man with respect to the ground

We have, 

Hence, the velocity with respected to ground is along the AC. Taking y components in eq. 1.  








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