An engineer in a locomotive sees a car stuck
on the track at a railroad crossing in front of
the train. When the engineer first sees the
car, the locomotive is 330 m from the crossing
and its speed is 21 m/s.
If the engineer’s reaction time is 0.44 s,
what should be the magnitude of the minimum deceleration to avoid an accident?
Answer in units of m/s
2
.