|What happens to an object that absorbs a lot of light?
|Question Date: 2017-01-26|
Basically, light is kind of energy.
Everything that absorbs the light will also absorb
the energy. What happens to an object after
absorbing the light will depend on what the object
is. For example, the crop, trees absorb the
light, and utilize them to produce the ingredients
for their growth. That's also why we live by
feeding on their fruits. Another example is the
man-made solar cell, which can convert the
absorbed energy into electricity (another kind of
energy). This is one of the examples we use
the solar energy. Most of the objects absorbing
the light will heat up to a certain degree.
That's why we feel warm under the sun in the cold
The object gets hot. Light is energy, so
absorbing energy means getting warmer.
Light travels with a momentum related to its
speed (the speed of light) and its wavelength,
since light travels in a wave. We look at
wavelength when assigning an energy to a type of
light, so short blue wavelengths will have a
higher energy than longer red wavelengths.
When a light hits the body of an object, the
energy the light carries transfers to the object.
The electrons feel this energy, and in response
get "excited" or get an increase of energy.
We know how excited electrons get by how much
energy the light carries. This excitement causes
the electron to go to a higher energy level or a
lower energy level.
When going up in energy levels, the electron
absorbs the light and has a higher energy, and
over time this energy goes back down due to
radiation emitted. When going down in energy
levels, a photon must be emitted with the
energy making up for this change in energy. We see
a general equation that a photon + electron at
lower energy level = electron at a higher energy
level . Looking at this, we get back to the
lower energy electron by emitted energy, in the
form of light.
Hope this answers your question!
There are many types of energy, including
heat, sound, and energy of motion (called kinetic
energy). Energy can’t be created or
destroyed, but it can be converted between the
different types of energy. For example,
rubbing your hands together quickly converts
energy of motion into heat energy as your hands
begin to feel warm.
Light energy is another type of energy. When
light hits an object, it either bounces off, and
stays as light energy, or it is absorbed by the
object. When it is absorbed, it is converted into
heat energy, and the object heats up. For example,
black objects absorb a lot of light, so if you
wear a black shirt on a sunny day, your shirt will
absorb the sunlight and convert it into heat,
making you feel hot!
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