Question

A car starts from rest at a stop sign. It accelerates at 2.0 m/s^2for 6.0 seconds, coasts for 2.0 s, and then slows down at a rate of 1.5 m/s^2 for the next stop sign.
How far apart are the stop signs?

Answer 1

divide it into three parts.

part one: acceleration.
find vf from a*t then find distance
part two: constant velocity
you know v, d=v*t
part three:
you know vi, vf, and a. Find distance
vf^2=vi^2+2ad

add the three distances

Answer 2

108

Answer 3

36