Question 1
2 marksA car is decelerating at 2.5 m/s².
Explain what this means.
Model answer
The car is slowing down: its velocity decreases by 2.5 m/s every second.
Explanation
An object that slows down is decelerating. A deceleration of 2.5 m/s² is the same as an acceleration of −2.5 m/s² when the direction of motion is taken as positive.
Mark scheme
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1 mark
the car is slowing down
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1 mark
its velocity decreases by 2.5 m/s every second
allow its speed decreases by 2.5 m/s each second