# Why is black colour good absorber and radiator of heat ?

I have read in my class 10th book and other books that black(usually dark) colour is avoided in summers and this is the reason why impure ice melts quickly .

I am wondering why ???

russ_watters
Mentor
By definition of the word "black".

HallsofIvy
Homework Helper
The color of any object is the light it reflects. An object is white if it reflects all or almost all of the light falling on it (and so absorbs little light). An object is black if it reflects no or very little light (and so absorbs almost all light). And, of course, light is energy. Absorbing little light only a slight increase in energy, absorbing a lot of light means a larger increase in energy and so a larger increase in heat.

By definition of the word "black".

Why is black colour good absorber and radiator of heat ? (usually dark colours)

How ? By definition ??

The color of any object is the light it reflects. An object is white if it reflects all or almost all of the light falling on it (and so absorbs little light). An object is black if it reflects no or very little light (and so absorbs almost all light). And, of course, light is energy. Absorbing little light only a slight increase in energy, absorbing a lot of light means a larger increase in energy and so a larger increase in heat.

Yes you are absolutely correct but why black colour absorbs large amount of light as compared to white .

By definition of the word "black".

The color of any object is the light it reflects. An object is white if it reflects all or almost all of the light falling on it (and so absorbs little light). An object is black if it reflects no or very little light (and so absorbs almost all light). And, of course, light is energy. Absorbing little light only a slight increase in energy, absorbing a lot of light means a larger increase in energy and so a larger increase in heat.

Got ya ! Thanks russ_watters . The answer to this question was by definition of word black .

Black is the color of objects that do not emit or reflect light in any part of the visible spectrum; they absorb all such frequencies of light. Although black is sometimes described as an "achromatic", or hueless, color, in practice it can be considered a color, as in expressions like "black cat" or "black paint".
http://en.wikipedia.org/wiki/Black

So black absorbs all the frequencies of light and doesn't reflect so more heat is produced in that , right .

Thanks to you all who replied .

Redbelly98
Staff Emeritus