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Why does black attracts heat and white reflects heat?
Question Date: 2018-03-07
Answer 1:

Objects that absorb light appear dark to us while objects that reflect light (and therefore heat) appear light (white) to us.

(Quick note: Light and heat are two different forms of the thing we call energy ).

Things that emit brighter light and more heat have higher energy.) Things that look lighter/whiter reflect many or all colors of light, and these emitted colors (colors given off by the object) come together to make these things look white. Black objects look black because they absorb all colors of light, and then give off the energy from the light in the form of heat. It is because of how well objects absorb or reflect light and heat that they appear either darker or lighter to us, not that they absorb heat because they're black. The colors are just representations of how well things retain energy.


Answer 2:

There are several ways that heat can be transmitted, but in this case we're talking about light, so it's helpful to talk about radiative heat, which is transmitted through infrared radiation that is invisible to our eye. In general, the color of something might not be as significant as the general material of an object. (For example, is it metal, is it plastic, and is it wood?) However, you could do a simple experiment with black and white paper. On average when compared to black paper, white paper reflects more light, so it absorbs less energy from visible and near-visible light. Because white paper absorbs less energy, it may not get as hot.


Answer 3:

Light is a type of energy. So is heat. Light that you see is light that is going into your eyes, which means that it is light that is not going into whatever you are seeing. White is a brighter color than black, so that means that something that is white is reflecting the light that you see when you see that it is white. That means that it is reflecting more energy, and gaining less heat.


Answer 4:

This is a really fun question because it touches on the difference between the two different places that color can come from. Color can come from light and it can also come from pigments. Light can come in any single color, in a mixture of all colors. When all colors of light combine, they make white light. Most lightbulbs produce white light which is why they appear white when we look at them. When there is no light, everything looks dark or black so we can call black the absence of light.

All of this changes when we talk about pigments. Pigments are dyes that we can use to make physical things look colorful. They can be found in our clothes, paints, and even our skin. Pigments reflect certain colors of light which makes its way into our eyes so we can see the color, and it absorbs others. When a pigment absorbs a color of light, it does not reach our eyes so we cannot see that color. Take a green book for example: it would absorb all colors of light besides green. That green light bounces off the green book, the green light makes its way into our eyes and we see the book as green.

Getting back to your question,how come black things absorb heat and white things reflect heat. We know that white objects have white pigments in them, meaning that they reflect white light. Since white is the combination of all light, that means that white things reflect all light and absorb none. Black objects do the opposite. We see them as black because they absorb all colors of light and reflect none. Thank you for your question!



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