why do black bodies absorb more heat?
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Let's first talk about light then we will proceed to heat.
The black body absorbs all the wavelengths of light that appears in the visible region of spectrum.
Now talking about why the black body gets heated up, I would like to say that the heating up process takes place in infrared region of spectrum not the visible spectrum.
Let's take an example of black brick.
Now the sunlight is falling on it. We know that energy is neither created nor destroyed; it is just transformed from one form to another.
Similarly, light is a form of energy.The black brick contains atoms and atoms contain electrons,protons and other sub-atomic particles. Now, when the light is falling on this black brick, all the wavelengths of light gets absorbed. These absorbed wavelengths start exciting the electrons( or simply molecules) present in the brick. The molecules start vibrating in their position and set a motion in the brick. This vibration is nothing but the heat generated.
You must have noticed that the sand gets heated up faster than the water in the sea. We know sand is solid while water is liquid. The molecules present in sand vibrate in their positions and have no way to move,so the sand gets heated up faster while in sea water though the molecules vibrate but it takes time for the water to get heated up since the molecules have free space to move.
Summing this up I can say that since sand is darker than water it will absorb the radiation faster than water. And water reflects the light back to the atmosphere.
Hope This Helps You!
The black body absorbs all the wavelengths of light that appears in the visible region of spectrum.
Now talking about why the black body gets heated up, I would like to say that the heating up process takes place in infrared region of spectrum not the visible spectrum.
Let's take an example of black brick.
Now the sunlight is falling on it. We know that energy is neither created nor destroyed; it is just transformed from one form to another.
Similarly, light is a form of energy.The black brick contains atoms and atoms contain electrons,protons and other sub-atomic particles. Now, when the light is falling on this black brick, all the wavelengths of light gets absorbed. These absorbed wavelengths start exciting the electrons( or simply molecules) present in the brick. The molecules start vibrating in their position and set a motion in the brick. This vibration is nothing but the heat generated.
You must have noticed that the sand gets heated up faster than the water in the sea. We know sand is solid while water is liquid. The molecules present in sand vibrate in their positions and have no way to move,so the sand gets heated up faster while in sea water though the molecules vibrate but it takes time for the water to get heated up since the molecules have free space to move.
Summing this up I can say that since sand is darker than water it will absorb the radiation faster than water. And water reflects the light back to the atmosphere.
Hope This Helps You!
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