A spring extends by 4 cm when a load of 10 N is applied. What load gives an extension of 10 cm if the limit of proportionality is not passed?
Answer and explanation
Correct answer: C. 25 N
- Step 1: By Hooke's law the extension is proportional to the load. Step 2. Load = 10 N x (10 / 4) = 25 N. Answer: 25 N. Why not the others: 40 N: That multiplies the load by 4, the first extension. 4 N: That divides the load by 2.5 instead of multiplying. 2.5 N: That divides 10 N by 4.
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