In This post you will get answer of Q.
A river is flowing from west to east with a speed $5,m,s^{-1}$. A swimmer can swim in still water at a speed of $10,ms^{-1}$.
If he wants to start from point $A$ on south bank and reach opposite point $B$ on north bank, in what direction should he swim?
Solution:
Here, Velocity of swimmer in still water,
$v_s = 10 ,ms^{-1}$
Velocity of water flowing in river,
$v_r = 5 ,m s^{-1}$
From figure,
$sin,theta=frac{v_{r}}{v_{s}}=frac{5}{10}=frac{1}{2}$
$theta=sin^{-1}left(frac{1}{2}right)$
$=30^{°}$ west of north
Solution:
Here, Velocity of swimmer in still water,
$v_s = 10 ,ms^{-1}$
Velocity of water flowing in river,
$v_r = 5 ,m s^{-1}$
From figure,
$sin,theta=frac{v_{r}}{v_{s}}=frac{5}{10}=frac{1}{2}$
$theta=sin^{-1}left(frac{1}{2}right)$
$=30^{°}$ west of north