Question

A car accelerates from rest at 7.2 m/s 2 . How much time does it need to attain a speed of 4 m/s? Answer in units of s.

Answer 1

The time is 0.6 sec.

Step-by-step explanation:

Given that,

Acceleration of car = 7.2 m/s²

Speed = 4 m/s

We need to calculate the time

Using equation of motion

`v=u+at`

Where, u = initial velocity

v = final velocity

a = acceleration

t = time

Put the value in the equation

`4=0+7.2* t`

`t=(4)/(7.2)`

`t=0.6\ sec`

Hence, The time is 0.6 sec.