As this two energy forms are introduced in the course, I began to question the relation of light and heat. Heat can be produced by light and light also can be produced by heat. Are they exist at the same time or one is the transform of the other? The answer can be explained with a loop.
If we start with light, the combination of visible light and infrared, it generates thermal radiation which cause increasing in temperature when applied to an object. Thermal radiation, as an electromagnetic wave, has greater energy (heat) with short wavelength. Because of its undulatory property and particle nature, the energy it contained is able to transmit to the object. When the energy of an object is high enough, visible light might be emitted from it. The tungsten filament in light bulbs is a good example. Even if the temperature is not very high, infrared light is constantly emitted when it’s above zero degree Kelvin. Therefore, light and heat coexist and they can be transformed from one to another.

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