Hooke's Law: Linear Extension Before Proportionality Limit

Steps:

• Hooke's Law states force (load) is proportional to extension, so graph is a straight line through origin.
• Limit of proportionality not reached means relationship remains linear, no deviation.
• Identify graph with straight line starting at origin for zero load-zero extension.
• Match to option B, which depicts this linear behavior.

Why B is correct:

• It shows a straight line through origin, directly following Hooke's Law (F = kx) where extension x is proportional to load F.

Why the others are wrong:

• A: Line not through origin, implying extension at zero load, violating Hooke's Law.
• C: Curved upward, indicating proportionality limit reached with non-linear behavior.
• D: Curved or scattered, suggesting inelastic or non-proportional response beyond limit.

Final answer: B