The swimmer crosses the river 240 m wide. The river flow speed is 1.2 m / s. The swimmer’s speed relative

The swimmer crosses the river 240 m wide. The river flow speed is 1.2 m / s. The swimmer’s speed relative to the water is 1.5 m / s and is directed perpendicular to the current vector. How many meters will the swimmer be swept away by the current by the time he reaches the opposite bank?

Given:

L = 240 meters – width of the river;

v1 = 1.5 meters per second – the swimmer’s speed relative to the water;

v2 = 1.2 meters per second – the speed of the river.

It is required to determine L1 (meter) – how many meters the swimmer will be carried by the current.

Let’s find the time it takes for a swimmer to cross the river:

t = L / v1 = 240 / 1.5 = 160 seconds.

During this time, the swimmer will be carried to a distance equal to:

L1 = t * v2 = 160 * 1.2 = 192 meters.

Answer: the swimmer will be carried by the current 192 meters by the time he reaches the opposite bank.