A metal bar of length 100mm is inserted between two rigid supports and its temperature is increased by $$10^o$$C. If the coefficient of thermal expansion is 12 x$$10^{-6}$$ per $$^o$$C and the Young’s modulus is 2 x $$10^{5}$$ MPa, the stress in the bar is

The axial movement of top surface of stepped column as shown in figure is