A car was traveling at 20m/s and slammed on the brakes causing the car to decelerate at a rate of - 2.5 m/s^2 before coming to a stop. What was the distance required for the car to stop? What formula must be used?

Answer: 160 m

Explanation: First find time or t using the formula for acceleration:

a = vf - vi / t

So t is equal to:

t = vf - vi / a

= 0 m/s - 20 m/s / - 2.5 m/s²

= 8 s

To find the distance use the formula for velocity:

v = d / t

Derive for d:

d = v x t

= 20 m/s x 8 s

= 160 m