Strain energy from force-extension graph for parallel springs

Steps:

• Total weight of 8.0 N divides equally between two identical parallel springs, so each experiences 4.0 N.
• From the graph, the extension of one spring at 4.0 N force is 0.030 m (assuming linear behavior).
• Strain energy in one spring is the area under the force-extension curve: (1/2) × force × extension.
• Calculate: (1/2) × 4.0 N × 0.030 m = 0.060 J.

Why A is correct:

• Matches the formula for elastic potential energy, U = (1/2)Fx, using the per-spring force and graph-derived extension.

Why the others are wrong:

• B uses total 8.0 N force instead of per spring.
• C likely misreads graph extension as 0.035 m.
• D doubles the correct energy, perhaps confusing total for both springs.

Final answer: A