A metallic bar of Young's modulus, \(0.5 × 10^{11}Nm^{−2}\) and coefficient of linear thermal expansion \(10^{−5^\circ}C^{−1}\), length 1m and area of cross section \(10^{−3}m^2\) is heated from \(0^\circ C\) to \(100^\circ C\) with out expansion or bending. The compressive force developed in it is: