Question

A race car starts from rest and accelerates uniformly to a speed of 40 m/s in 8.0 seconds. How far will the car travel during the 8 seconds?

Answer 1

There are two steps to this problem: finding the acceleration and then the distance. The distance covered is `160 m`.

Explanation:

First use the formula `v = u + at` to calculate the acceleration. The initial velocity, `u`, is `0 ms^-1`, and we are given the final velocity `v = 40 ms^-1` and the time taken, `t=8s`.

Rearranging, `a = v/t = 40/8 = 5ms^-2`

To find the distance travelled, use the formula `d = ut + 1/2at^2`

The initial velocity is still `0 ms^-1`, so

`d = 1/2at^2 = 1/2*5*8^2 = 160 m`