Question

A car travels from Bangalore to Mumbai and returns in $20hours$. What is the average velocity and average speed of the car if odometer reading of the car, when it started was $2200km$ and when finished was $3800km$?

• A. $\text{Average velocity = 0 kmph}$
  $\text{Average speed = 0 kmph}$
• B. $\text{Average velocity = 0 kmph}$
  $\text{Average speed = 80 kmph}$
• C. $\text{Average velocity = 80 kmph}$
  $\text{Average speed = 80 kmph}$
• D. $\text{Average velocity = 80 kmph}$
  $\text{Average speed = 0 kmph}$

Answer 1

The correct option is B $\text{Average velocity = 0 kmph}$

$\text{Average speed = 80 kmph}$
Given, the displacement of the car = $0km$
(As the initial position is the same as the final position)

Initial odometer reading = $2200km$,
Final odometer reading = $3800km$.
$\therefore$ the distance covered = $3800-2200=1600km$
Time taken = $20hours$

We know:
$\text{Average velocity}=\frac{\text{Total displacement}}{\text{Total time}}$ $=0$
$\text{Average speed}=\frac{\text{Total distance}}{\text{Total time}}$
$=\frac{1600}{20}=80\text{kmph}$

$\therefore$ the average velocity of the car is $0\text{kmph}$, and the average speed of the car is $80\text{kmph}$