A spring of constant 100 N/m is stretched by 0.05 m. How much energy is stored in it?
Answer and explanation
Correct answer: A. 0.125 J
- Step 1: Elastic energy = ½kx². Step 2. E = ½ × 100 × 0.05² = 0.125 J. Answer: 0.125 J. Why not the others: 0.25 J is what you get if you forget the factor ½. 2.5 J is what you get if you forget to square the extension. 5 J is what you get if you give the force instead.
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