Question

A steel rod of dimensions 4×4 cm2 is tightly fixed between two support and is not allowed to expand. It is heated through 2°C. Thermal stress developed is........10 ^6 N/m2

Answer 1

A steel rod of dimensions 4×4 cm2 is tightly fixed between two support and is not allowed to expand. It is heated through 2°C. Thermal stress developed is........10 ^6 N/m2

formula of Thermal stress , S = Yα∆T

where , Y is Young's modulus of material, α is linear coefficient of thermal expansion and ∆T is the change in temperature.

value of Y and α are experimental datas.

i.e., α = 7.2 × 10^-5 /°C

and Y = 2 × 10¹¹ N/m²

change is temperature is already given, i.e., ∆T = 2°C

now, thermal stress = 2 × 10¹¹ × 7.2 × 10^-5 × 2

= 28.8 × 10^6 N/m²

hence, Thermal stress developed is 28.8 × 10^6 N/m²