A body moves in a circle of radius 20 m at 20 m/s. What is its centripetal acceleration?
Answer and explanation
Correct answer: A. 20 m/s²
- Step 1: a = v²/r. Step 2. a = 20² ÷ 20 = 20 m/s². Answer: 20 m/s². Why not the others: 1 m/s² is what you get if you forget to square the speed. 8000 m/s² is what you get if you multiply by the radius. 0.05 m/s² is what you get if you invert the formula.
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