Question 5
An object starting from rest travels for 10 s with an acceleration of 0.5 m s-2. What is its velocity at the end of those 10 seconds?
The right answer is the one marked above.
5 m s-1. Rearranging acceleration = change in velocity ÷ time gives change in velocity = acceleration × time:
change in velocity = 0.5 m s-2 × 10 s = 5 m s-1
The object started from rest — an initial velocity of 0 — so the final velocity is 0 + 5 = 5 m s-1. An acceleration of 0.5 m s-2 means the velocity rises by 0.5 m s-1 each second, which over 10 s comes to 5 m s-1.