A circular metallic rod of length 250 mm is placed between

A circular metallic rod of length 250 mm is placed between two rigid immovable walls as shown in the figure. The rod is perfect contact with the wall on the left side and there is a gap of 0.2 mm between the rod and the wall on the right side. If the temperature of the rod is increased by 200°C, the axial stress developed in the rod is _______ MPa. Young's modulus of the material of the rod is 200 GPa and the coefficient of thermal expansion is10^-5per°C.

lαt = 250 × (10^–5)(200)

=	1	= 0.5 mm > gap
	2

Deformation prevented = 0.5 – 0.2 = 0.3 =	Pl
	AE

⇒ 0.3 =	σ(250 + 0.2)
	200 × 10³

σ = 239.8 MPa