A car drives around a circular curve of radius 4 m at 8 m/s. What is its centripetal acceleration?
Answer and explanation
Correct answer: C. 16 m/s^2
- Step 1: Centripetal acceleration is a = v^2 / r.
- Step 2: a = 8^2 / 4 = 16 m/s^2.
Answer
16 m/s^2.
Why not the others: The speed is squared and divided by the radius; v/r, v^2 r and v r are different quantities.
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