Question

a stress of 1 kg metre per meter square is applied to a wire of which youngs modulus is 10 raise to 11. find the percentage increase in length

Answer 1

F/A = 1 kg/mm∧2 = 10∧6 kg/m∧2

Y = 10∧11 N/m∧2

Y = (F/A)/(ΔL/L)

=> (ΔL/L) = (F/A)/Y = 10∧6/10∧11 = 10∧-5

Therefore, (ΔL/L) × 100% = 10∧-3 %