Answer:
0.1m/s²
Step-by-step explanation:
Using the equation of motion
V = u+at
V is the final speed = 0.9m/s
Initial speed u = 0.5m/s
Time = 4secs
Get the acceleration
0.9 = 0 5+4a
0.9-0.5 = 4a
0.4 = 4a
a = 0.4/4
a = 0.1m/s²
Hence the acceleration is 0.1m/s²