It is said that at higher temperatures an object radiates red color the most. So does an object that is red in color is supposed to have a higher temperature?
1 Answer
Not true in general.
Explanation:
There is more than one way to generate the perception of colors: by radiation, by reflection, by refraction, and by absorption of light.
Most colors we see are due to absorption of light incident on a surface. A paper is red because it absorbs all other colors of the light but red, so you only see red light reflected. However, the red color you see on a bird's feather could be a result of constructive inference of red light reflected, but not so for other colors reflected--this has a lot to do with the microxcopic features of the feathers.
Different colors that you see a room held at constant temperatue should have the same temperature because the surfaces they are coming from have reached thermal equilibrium with the room.
The red color emitted by a hot plate you see on the kitchen stove is because red hot iron at around 1000K temperature radiates most energy in the red light region. However, at even higher temperature, other colors dominate over red. This fact is known as blackbody radiation. See below:
Colors of blackbody radiation - red is not the highest temperature, though much higher than room temperature for sure.
