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Please consider a closed room with light reflecting walls and in the centre of the room there is a Lighting Bulb. Now if I switch on the bulb, the room is obviously illuminated with light. When I switch off the bulb, since the light photon cannot escape the room, will the room be infinitely illuminated?


marked as duplicate by John Rennie, RedGrittyBrick, Kyle Kanos, Qmechanic Oct 22 '15 at 10:35

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