Question

a wire 3m long and 0.635 sq.cm in cross-section is found to stretch 0.3 cm under a tension of 1200 kg. what is the youngs modulus of the material of the wire?

Answer 1

Y = FL/A∆L ⇒ ∆L/L = F/Ay σ = ∆D/D/∆L/L ⇒ ∆D again, ∆A/A = 2∆r/r ⇒ ∆A = 2∆r/r