How much gravitational potential energy does a 2 kg mass gain when lifted 6 m? (take g = 10 m/s²)
Answer and explanation
Correct answer: B. 120 J
- Step 1: ΔPE = mgh. Step 2. ΔPE = 2 × 10 × 6 = 120 J. Answer: 120 J. Why not the others: 12 J is what you get if you leave out g. 60 J is what you get if you use ½mgh. 30 J is what you get if you divide by the mass.
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