The pressure that has to be applied to the ends of a steel wire of length $10$ $cm$ to keep its length constant when its temperature is raised by ${100^ \circ }C$ is: (For steel Young's modulus is $2 \times {10^{11}}\,\,N{m^{ - 2}}$ and coefficient of thermal expansion is $1.1 \times {10^{ - 5}}\,{K^{ - 1}}$ )