Question 15
ElasticityThe diagram above represents the graph of the force (F) applied in stretching a spiral spring against the corresponding extension(X). The force constant of the spring is
- A.20 Nm−1.
- B.40 Nm−1.
- C.30 Nm−1.
- D.10 Nm−1.
Show the answer and explanation
Answer: A (20 Nm−1.)
Explanation
The force constant is the slope of the F–X graph. The line reaches F = 120 at X = 6, so k = 120 ÷ 6 = 20 N m−1 (for example 40 at 2).