A cylinder of cross-section area A has two pistons of negligible mass separated by distances l loaded with spring negligible mass. An ideal gas at temperature T₁ is in the cylinder where the springs are relaxed. When the gas is heated by some means its temperature becomes T₂ and the springs get compressed by $\frac{l}{2}$ each. If P₀ is atmospheric pressure and spring constant $k=\frac{2P_{0}A}{l}$ then the ratio of T₂ and T₁ is _______