Question

Two rods of different material having coefficient of linear expansion α₁ and α₂ and Young’s modulus Y₁ and Y₂ respectively are fixed between two rigid walls. The rods are heated to same high temperature. If α₁:α₂ ∷ 2 ∶ 3 the thermal stress in two rods is the furid same, then the rate Y₁/Y₂.

Answer 1

Stress = Y × strain

∴ Y₁α₁t₁ = Y₂α₂t₂

∴ Y₁α₁ = Y₂α₂

Or \(\frac{Y_1}{Y_2}\) = \(\frac{α_1}{α_2}\)

= \(\frac{3}{2}\)