Answer:
-3.125m/s^2
Step-by-step explanation:
Average acceleration = v-u /t
That is initial final velocity v minus initial velocity u divided by the time t In seconds .
From the question,
v =9.5m/s
u =12m/s
t =0.8 secs
Using the above formula,
We have
average a = 9.5 -12 /0.8
= -2.5/0.8
= -3.125m/s^2
Negative answer indicates that the train was decelerating
