What force gives a mass of 9 kg an acceleration of 9 m/s²?
Answer and explanation
Correct answer: A. 81 N
- Step 1: Newton's second law: F = ma. Step 2. F = 9 × 9 = 81 N. Answer: 81 N. Why not the others: 1 N is what you get if you divide the mass by the acceleration. 18 N is what you get if you add the numbers. 810 N is what you get if you multiply by g as well.
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