Practice question · Multiple choice
A car speeding up and a car slowing down can both have positive acceleration. How?
Hints
- Take rightward as positive and consider a car moving LEFT and braking.
- Compare the signs of and .
Show the answer
A. Because the sign is the direction of the change, not the motion
Why
Speeding up means and share a sign; slowing means they differ. "Deceleration" names the relationship, not a sign, which is why it is avoided in careful work.
Practise Kinematics in One Dimension
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