Question

A motorcycle is moving with a velocity $80 km / hr$ ahead of a car moving with a velocity of $65 km / hr$ in the same direction. What is the relative velocity of the motorcycle with respect to the car:-

• A. $15\,km/h$
• B. $20\,km/h$
• C. $25\,km/h$
• D. $145\,km/h$

Answer 1

Answer: (A)

As in this question
speed of the motorcycle $=80 km / hr$
speed of the car $=65 km / hr$
they are moving in the same direction with motorcycle moving ahead
we need to calculate the relative velocity of the motorcycle with respect to the car
as we know $V_{a b}=V_{a}-V_{b}$
here $V_{a b}$ is the relative velocity of the motorcycle with respect to the car
$V _{ a }$ is the velocity of the motorcycle
$V_{b}$ is the velocity of the car
so $V _{ ab }=(80-65) km / hr$
so $V_{a b}=15 km / hr$