Question

Two cars $A$ and $B$ moving in opposite direction along a straight road with constant velocities of $20\text{m/s}$ and $40\text{m/s}$ respectively. Velocity of $B$ with respect to $A$ is

• A. $20\text{m/s}$
• B. $30\text{m/s}$
• C. $60\text{m/s}$
• D. $80\text{m/s}$

Answer 1

The correct option is C $60\text{m/s}$

The relative velocity of $B$ with respect to $A$ is given as
$v_{BA}=v_B–v_A$
Since, they are in opposite directions
$v_{BA}=40–(–20)=60\text{m/s}$
Therefore, the correct answer is (c)