Question

A swimmer is capable of swimming 1.65 m/s in still water . If she swims directly across a 180m wide river whosecurrent is 0.85m/s ,how far downstream (from a point opposite her starting point) will she reach?

Answer 1

Given that,

Speed of swimmer in still water is 1.65 m/s

Width of river is 180 m

Speed of river is 0.85 m/s

To find,

How far downstream (from a point opposite her starting point) will she reach?

Solution,

If t is the time taken by the swimmer to cross the river is calculated as :

$t=\dfrac{180}{1.65}\\\\t=109\ s$

Let x is the distance from a point opposite her starting point. It is calculated by the product of speed of river and time taken to cross the river.

$x=0.85\times 109\\\\x=92.65\ m$

So, she will reach 92.65 m downstream.