A 100 m long wire having cross-sectional area 6.25 ×10⁻⁴ m² and Young’s modulus is 10¹⁰ N m⁻² is subjected to a load of 250 N, then the elongation in the wire will be :
Options

Question

A 100 m long wire having cross-sectional area 6.25 ×10⁻⁴ m² and Young’s modulus is 10¹⁰ N m⁻² is subjected to a load of 250 N, then the elongation in the wire will be :

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 D: 4 ×10⁻³ m. Therefore the correct answer is D.