An automobile and train move together along
parallel paths at 21.8 m/s.
The automobile then undergoes a uniform
acceleration of −4 m/s
2
because of a red light
and comes to rest. It remains at rest for 19.1 s,
then accelerates back to a speed of 21.8 m/s
at a rate of 3 m/s
2
.
How far behind the train is the automobile
when it reaches the speed of 21.8 m/s, assuming that the train speed has remained at
21.8 m/s?
Answer in units of m