Question

A car at rest ends accelerates for 12 seconds. After this time the car is going 36 m/s. What was its acceleration?

Answer 1

Acceleration is defined as velocity per unit time.

$Acceleration=\frac{Velocity}{time}$

$a=\frac{dv}{dt}$

Here, a=acceleartion,

v=velocity=36 m/s

t=time=12 s

$a=\frac{dv}{dt}$

$a=\frac{36}{12}$

$a=3 ms⁻²$

A car at rest ends accelerates for 12 seconds. After this time the car is going 36 m/s. So acceleration that is a=3 ms⁻².

Answer 2

Using the equation of motion:

$a = \frac{v-u}{t}$

where $a$ is acceleration, $v$ is final velocity, $u$ is initial velocity, and $t$ is time

Given values are:

$t = 12 sec, v= 36 m/s, u = 0  $ (because initially car was at rest)

Substituting the values in the formula:

$a = \frac{36-0}{12} = 3 m/s^{2}$

Hence, the acceleration of the car is $3 m/s^{2}$.