Question

A car accelerated from 45 m/s to 0 m/s in 10 seconds. what is the average acceleration of the car?

Answer 1

constant acceleration is defined as time rate change of velocity.

Answer 2

Answer : The average acceleration of the car is $-4.5m/s^2$.

Solution : Given,

Initial velocity = 45 m/s

Final velocity = 0 m/s

Time = 10 seconds

Average acceleration : It is defined as the change in velocity divided by the time.

Formula used :

$a=\frac{\Delta V}{t}=\frac{V_{final}-V_{initial}}{t}$

where,

a = average acceleration

t = time

$V_{initial}$ = initial velocity

$V_{final}$ = initial velocity

Now put all the given values in this formula, we get the average acceleration.

$a=\frac{(0m/s)-(45m/s)}{10s}=-4.5m/s^2$

Acceleration is in negative that means the speed of car is slowing down.

Therefore, the average acceleration of the car is $-4.5m/s^2$.