a=(v-u)/t
We know a=2.5, v=40, u=10, so:
2.5=(40-10)/t
2.5t=40-10
2.5t=30
Divide both sides by 2.5
t=12 It takes 12 seconds for the car to reach 40m/s
To find out how far it went, you do:
d=v+1/2 at^2
d=10+1/2(2.5)(12)^2
d=10+1/2(2.5)(144)
d=10+(1.25)(72)
d=10+90
d=100m
Hope this helps :)
