Two cars start from rest and accelerate uniformly. Car A reaches 20 m/s in 5 s. Car B reaches 30 m/s in 10 s. Which car has the GREATER acceleration?
ACar A (4 m/s² vs 3 m/s²)
BCar B (since it reaches a higher speed)
CSame acceleration
DCannot be compared
Answer & Solution
Correct answer: A. Car A (4 m/s² vs 3 m/s²)
a_A = 20/5 = 4 m/s². a_B = 30/10 = 3 m/s². Car A has greater acceleration even though Car B reaches higher final speed (because Car B's increase is spread over more time). Acceleration is rate of change of velocity, not final velocity.
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