|WHY BLACK COLOR PAPER GET WARM AND WHITE COLOR
PAPER GET COOL WHEN EXPOSE TO SUN?
|Question Date: 2013-02-20|
When sunlight falls on an object, one of
three things can happen: the light can be
reflected back to where it came from, the light
can be transmitted through the object, or the
light can be absorbed.
When light is absorbed, the object will heat up.
Now black paper absorbs most light, whereas
white paper reflects some of the incident
radiation (light). Hence, black heats up more
We should be very careful with how to phrase
this question. White paper does not actually get
cool when it's exposed to the sun! It still gets
warm, just not AS warm as black paper does.
Black paper gets warmer than white paper when
exposed to sunlight because black absorbs more
radiation (in the form of heat and light energy)
from the sun. White paper, on the other hand,
reflects more of the heat and light energy.
Light is energy, as is heat. Dark colors
absorb light, while light colors bounce it away.
This means that something dark will soak up
light and become hot when light shines on it,
while something light will remain cool.
Have you tried doing an experiment to see if
you can reproduce this effect? Also, I don't
know if the white paper would get cool, or just
that it wouldn't get as hot as black paper.
Although I'm not sure how significant the
difference would be, my guess is that, on
average when compared to black paper, white
paper reflects more light, so it absorbs less
energy from visible and near-visible light.
Because it absorbs less energy, it doesn't get
Heat and light are both different types of
energy. Light energy can be
converted into heat energy. The black paper
absorbs all of the
sunlight and converts it into heat, so the paper
gets warm. The white
paper reflects almost all of the sunlight, so
the light is not
converted into heat and the temperature of the
paper does not increase
noticeably. What happens if you put colored
paper in the sun? It
should get warmer, but not as warm as the black
paper, because it is
only absorbing some of the colors of light and
converting them to
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