What Happens to Photon Energy When Light is Turned Off?

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When light is turned off, the energy of photons is absorbed by surrounding surfaces, such as walls, which then heat up. According to the law of conservation of energy, this energy is not destroyed but transferred. The absorbed energy may be re-emitted as infrared radiation. Once photons are absorbed, they cease to exist, and their energy is fully transferred to the absorbing material. Thus, no energy is lost in the process.
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Light consists of photon
Photon is carrier of energy
When lights are switched off where had the energy of photon gone
According to law of conservation of energy
Energy can't be destroyed
In darkness, are they any radiation due to conversion of energy??
 
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The visible light is absorbed by the walls, heating them up. Often the energy is re-emitted in the infra-red.
 
gokhul said:
When lights are switched off where had the energy of photon gone

As Dave said, the energy of the photons already created and in flight when the light is switched off are absorbed by the walls and anything else in line-of-sight of the bulb. After that, well, no more photons are being generated from the light source.
 
Drakkith said:
As Dave said, the energy of the photons already created and in flight when the light is switched off are absorbed by the walls and anything else in line-of-sight of the bulb. After that, well, no more photons are being generated from the light source.
Photon contains energy ,an energy can't be destroyed or if they are absorbed by walls do they posses any energy or reemit as infra red radiation
 
gokhul said:
Photon contains energy ,an energy can't be destroyed or if they are absorbed by walls do they posses any energy or reemit as infra red radiation

The photon no longer exists after absorption. The energy it contained is completely transferred to the wall, so no energy is lost.
 
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