Question

A car has a constant acceleration of 5 m/s/s. At some time it is traveling at 40 m/s. How fast will it be going, one second later?
a.) 30 m/s
b.) 40 m/s
c.) 45 m/s
d.) 200 m/s

Answer 1

well velocity increases by 5m/s every second, right?

Answer 2

Understanding what acceleration means gives you the immediate answer without any calculation.
If at any one time, the velocity is 40 m/s and that velocity changes 5 m/s every second, then one second later it must be 45 m/s

Answer 3

a*t = 40.
5t = 40, t = 8 s.

V = a*t = 5(8+1) = 45 m/s.