Below Fig. shows a rigid bar hinged at A and supported in a horizontal position by two vertical identical steel wires. Neglect the weight of the beam. The tension $${T_1}$$ and $${T_2}$$ induced in these wires by a vertical load P applied as shown are

Determine the temperature rise necessary to induce buckling in a 1 m long circular rod of diameter 40 mm shown in the figure below. Assume the rod to be pinned at its ends and the coefficient of thermal expansion as 20 $$ \times $$ 10^-6/^oC. Assume uniform heating of the bar.