Q. A stepped bar of steel consists of a pmormtion with cross section area 500 mm2 connected to a portion with cross section area 1000 2. Each portion has a length of 1 m. The modulus of elasticity of steel is200 GPa. The maximum elongation of the bar by applying an axial tensile force at the ends without exceeding a stress of 100 MPa is   mm. (Solved)