Two bulbs have filaments of lengths, Emissivity's and diameters in the ratio of 2: 1. If ratio of their powers is 1 :2 then, ratio of their temperatures is

Two bulbs have filaments of lengths, Emissivity's and diameters in the

1.	Two bulbs have filaments of lengths, Emissivity's and diameters in the ratio of 2: 1. If ratio of their powers is 1 :2 then, ratio of their temperatures is
Answer» `1:1` `1:2` `2:1` `1:4` ANSWER :B