physics
posted by ricajane on .
a bus is moving on a straight highway at 12m/s. as it approaches the total gate, it decelerates at 2.5 m/s2 in 5 seconds. what is the final velocity of the bus?

Given:
Vi = 12 m/s
a =  2.5 m/s2
t = 5s
Required: Vf (final velocity)
Solution:
a=Vf^2  Vi^2 / t
2.5 m/s = Vf^2  (12m/s)^2 / 5s
2.5 m/s = Vf^2  144m^2/s^2
2.5m/s over 144 m^2/s^2 = Vf^2
0.13 m/s = Vf 
You must mean toll gate.
After decelerating 5 s at 2.5 m/s^2, it will have reduced its velocity by 12.5 m/s, and will be going backwards, at 0.5 m/s.
A rather strange situation.