An aluminium rod with Young's modulus Y=7.0×10¹⁰ N m⁻² undergoes an elastic strain of 0.04%. The energy stored per unit volume is:
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An aluminium rod with Young's modulus Y=7.0×10¹⁰ N m⁻² undergoes an elastic strain of 0.04%. The energy stored per unit volume is:

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 A: 5600. Therefore the correct answer is A.