The ratio of the thermal conductivities of two different materials is 1 : 2. The thermal resistance of the rods of these materials having the same thickness are equal. Find the ratio of the length of rods.

The ratio of the thermal conductivities of two different materials is

1.	The ratio of the thermal conductivities of two different materials is 1 : 2. The thermal resistance of the rods of these materials having the same thickness are equal. Find the ratio of the length of rods.
Answer» SOLUTION :Thermal RESISTANCE `R = X // KA, x_1 // K_1 A_1 = x_2 // K_2A_2, x_1 // x_2 = K_1 // K_2 = 1//2`