Question 1
The table shows how the velocity of an object travelling along a straight path changed with time.
| Time t (s) | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|---|
| Velocity v (m s-1) | 0 | 2 | 4 | 6 | 8 | 10 | 12 |
What is the object's acceleration?
The right answer is the one marked above.
2 m s-2. Acceleration is the change in velocity divided by the time taken:
acceleration = (12 − 0) m s-1 ÷ 6 s = 2 m s-2
An acceleration of 2 m s-2 means the velocity grows by 2 m s-1 every second — which is exactly what the table shows. 12 m s-2 is the change in velocity, not the acceleration; it still has to be divided by the time.