A body has an initial velocity of 12 m s^-1 and is brought to rest over a distance of 45 m. What is the acceleration of the body?

-1.46 m/s^2

Explanation:

Write down what is given first:

v0 = 12 m/s

vf = 0 m/s

d = 45 m

We are trying to find acceleration, so we will use the equation vf^2 = v0^2 + 2ad

Plug in the values we have:

0^2 = 12^2 + (2 x 45 x a)

a = - 1.46 m/s^2

Note that this acceleration is negative because the body is slowing down, so the acceleration with be negative, because the change in velocity is negative.