Question

A race car starts from rest and speeds up uniformly to the right until it reaches a maximum velocity of 60\,\dfrac{\text m}{\text s}60 s m ​ 60, space, start fraction, m, divided by, s, end fraction in 15 \,\text s15s15, space, s. What is the acceleration of the race car?

Answer 1

a car starts from rest so its initial speed is ZERO

`v_i = 0 m/s`

now car accelerates uniformly and reached to final speed 60 m/s

so we can say

`v_f = 60 m/s`

time taken to increase the speed is given as

`\Delta t = 15 s`

now we know that acceleration is rate of change in velocity

`a = (v_f - v_i)/(\Delta t)`

`a = (60 - 0)/(15) = 4 m/s^2`

so the acceleration of the car must be 4 m/s^2