Two spheres of the same material have radii 1m and 14m and are at temperature 4000 K and 2000 K respectively. What is the ratio of energy radiated by each of them ?

Two wires made from the same material have their lengths L and 2L and the radii 2r and r respectively. What is the ratio of their elongation if they are stretched by the same force ?

There are two wires of the same material . Their radius and length are in the ratio 1:2 If the extension produced are equal, what is the ratio of the loads

Two rods 1 and 2 of same length have same temperature difference between their ends. Their thermal conductivities are K_1 and K_2 , and cross sectional areas A_1 and A_2 respectively. What is the required condition for the same rate of heat conduction in them ?

Two wires of the same material have their lengths in the ratio 3:2 , diameters in the ratio 3:2 and streching forces in the ratio 3:4 . What is the ratio of their extension

Two wires have diameters in the ratio 1:2 , length in the ratio 3:4 and young's moduli in the ratio 2:3. What is the ratio of elongations produced in the wires if they are subjected to the same streching force ?