How much gravitational potential energy does a 5 kg mass gain when lifted 27 m? (take g = 10 m/s²)
Answer and explanation
Correct answer: B. 1350 J
- Step 1: ΔPE = mgh. Step 2. ΔPE = 5 × 10 × 27 = 1350 J. Answer: 1350 J. Why not the others: 135 J is what you get if you leave out g. 675 J is what you get if you use ½mgh. 54 J is what you get if you divide by the mass.
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