A man who can swim at the rate of 2 km/hr (in still river) crosses a river to a point exactly opposite on the other bank by swimming in a direction of 120° to the flow of the water in the river. The velocity of the water current in km/hr is

Question

A man who can swim at the rate of 2 km/hr (in still river) crosses a river to a point exactly opposite on the other bank by swimming in a direction of 120° to the flow of the water in the river. The velocity of the water current in km/hr is  (A)  (B)  (C)  (D)

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<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/a1d11783dc57b429c0d676c2830fee86-.png" /> Let speed of current be u For net velocity of man to be normal to river flow 2 cos 60°=u or u=1 km/hr

Q. A man who can swim at the rate of $2 km / h r$ (in still river) crosses a river to a point exactly opposite on the other bank by swimming in a direction of $12 0^{\circ}$ to the flow of the water in the river. The velocity of the water current in km/hr is ________

Let speed of current be $u$
For net velocity of man to be normal to river flow
$2 cos 6 0^{\circ} = u$
or $u = 1 km / h r$

Q. A man who can swim at the rate of 2km/hr (in still river) crosses a river to a point exactly opposite on the other bank by swimming in a direction of 120∘ to the flow of the water in the river. The velocity of the water current in km/hr is ________

Let speed of current be u For net velocity of man to be normal to river flow 2cos60∘=u or u=1km/hr

Q. A man who can swim at the rate of $2 km / h r$ (in still river) crosses a river to a point exactly opposite on the other bank by swimming in a direction of $12 0^{\circ}$ to the flow of the water in the river. The velocity of the water current in km/hr is ________

Let speed of current be $u$
For net velocity of man to be normal to river flow
$2 cos 6 0^{\circ} = u$
or $u = 1 km / h r$