Question

A motorcycle is moving with a velocity 80 kmph ahead of a car moving with a velocity of 65 kmph in the same direction. What is the relative velocity of the motorcycle with respect to the car (A) 15 kmph (B) 20 kmph (C) 25 kmph (D) 145 kmph​

Answer 1

Given:

A motorcycle is moving with a velocity 80 kmph ahead of a car moving with a velocity of 65 kmph in the same direction.

To find:

Relative velocity of the motorcycle with respect to the car?

Calculation:

Since both the vehicles are moving in the same direction, we will consider their signs to be positive.

Relative velocity of motorcycle with respect to the car will be :

$\rm \: v_{b.c} = v_{bike} - v_{car}$

$\rm \implies \: v_{b.c} = + 80- ( + 65)$

$\rm \implies \: v_{b.c} = 80- 65$

$\rm \implies \: v_{b.c} = 15 \: kmph$

So, Velocity of Bike w.r.t Car is 15 kmph (OPTION A).