# Kinematics | Problem 1.7

Irodov I.E. - Problems in General Physics (1981)

## PHYSICAL FUNDAMENTALS OF MECHANICS | Kinematics

### Problem 1.7

Two swimmers leave point $$A$$ on one bank of the river to reach point $$B$$ lying right across on the other bank. One of them crosses the river along the straight line $$AB$$ while the other swims at right angles to the stream and then walks the distance that he has been carried away by the stream to get to point $$B$$. What was the velocity $$u$$ of his walking if both swimmers reached the destination simultaneously? The stream velocity $$v_0 = 2.0$$ km/hour and the velocity $$v'$$ of each swimmer with respect to water equals $$2.5$$ km per hour.