The load versus strain graph for four wires of the same material is shown in the figure. The thickest wire is represented by the line :-
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Question

The load versus strain graph for four wires of the same material is shown in the figure. The thickest wire is represented by the line :-

G1 Physics · Accepted Answer

Use stress σ=F/A, strain ε=ΔL/L and Young's modulus Y=σ/ε. For a uniform segment, ΔL=FL/(AY); for thermal restraint, thermal strain αΔT produces stress YαΔT. Evaluating the given data/statements gives OD. Therefore the correct answer is C.