# Crossing a River

A swimmier heads across a river, swimming at 1.20m/s relative to still water. It arrives at a point 67.0 m downstream from the oint directly across the river, which is 100.m wide. What is the speed of the river current?

Here's what I did:

tan^-1(67/100)
theta = 33.82 degrees

Vx = Vxocos(33.82)
Vx = 1.20m/s * cos(33.82)
Vx = 0.997m/s

and since the current is moving in the opposite direction it would be -0.997m/s.

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it's wrong.

So obviously my method of getting the answer was flawed aswell. Is there another way to solve this problem?

Determine the time it takes to cross the river. In this period the swimmer drifts 67 m. Solve for the current speed.

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sundrops said:
it's wrong.

So obviously my method of getting the answer was flawed aswell. Is there another way to solve this problem?
1.20 m/s is the speed of the swimmer in still water. Not his total speed. His velocity is 1.20 m/s in the x-direction (direction across river), and v in the y-direction(along the river), where v is the river speed. How long does it take him to cross the river?