Infrared waves are widely used for quick heating objects, but a quick look at electromagnetic spectrum astonished me and raised a question that how come an infrared wave with lower energy compared to visible light is able to heat objects.Is there anything here related to resonance ...??
When you say:
an infrared wave with lower energy compared to visible light
I'm guessing you're referring to the photon energy:
$$ E = h\nu $$
Visible light has a higher frequency than IR light, so the energy per photon of visible light is higher than IR light. However this is not related to the energy carried by the wave. The power transmitted by a wave is the energy per photon multipled by the number of photons per second, and we can adjust the number of photons per second simply by adjusting the intensity of the radiation. So a high intensity IR wave can transmit more power than a low intensity visible wave.
We tend to use IR for heating things simply because it's easier to generate high intensity IR than high intensity light. Many of the radiation sources we use approximate black bodies, and the peak frequency of black body radiation is proportional to the black body temperature. So to generate visible light requires a considerably higher temperature than to generate IR.
protected by ACuriousMind♦ Feb 11 '17 at 23:32
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