A Room of Infinite Reflection: How Bright Will It Get?

AI Thread Summary
In a room with perfect reflectors on all surfaces and a continuously glowing light bulb, the final illumination will not increase beyond the brightness of the bulb itself. The light will be reflected indefinitely, but the bulb will absorb the light energy, converting it to heat. As a result, the temperature in the room will rise significantly, potentially causing the bulb to overheat and explode, leading to a complete absence of light. Once the bulb fails, the room will descend into darkness as the existing light is absorbed by the remnants of the bulb, which will release heat energy. The discussion highlights the paradox of light reflection and absorption in a closed system, emphasizing the thermal consequences rather than sustained illumination.
vikasj007
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What if you are in a room and the walls, floor and ceiling are all perfect reflectors, and there's a light on in the middle of the room. How bright will it get in there?
 
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I believe it won't get any brighter, but *you* will eventually get pretty warm. You're the only thing in the room that will absorb the light and convert it to heat.
 
DaveC426913 said:
I believe it won't get any brighter, but *you* will eventually get pretty warm. You're the only thing in the room that will absorb the light and convert it to heat.

Sounds like standing on the inside of an Easy Bake Oven, doesn't it?
 
i think i had made a mistake while posting the question.

the corrected form of thie question is as follows-

there is a room in which all the walls and roof and floor are perfect reflectors, and a source of light , a bulb, is placed inside the room which is glowing constantly, what will be the final lumination of the room.



i am also going to change the question in the first post, so do note the change.
 
I don't know about light, but it will get pretty hot in there. Ever put tin foil over a lightbulb? (warning do not actually put tinfoil over a lightbulb unless you are prepared to risk blowing the socket and possibly starting a fire)
 
Answer to original:
They would be just as bright as the bulb emmitting the light.

Here's a question, what color will the mirrors be?


Answer:
They would be the color of the light emitting, white.
 
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actally, the final illumination of the room would be, zero. the room will be filled with darkness.

as the light bulb emits light, it is completely reflected by the walls and the floor, the only thing which will absorb the light is the bulb. it will get very very hot and eventually explode. after that no more light will enter the room, and the exsisting light in the room will gradually be absorbed by the glass pieces which in turn will release it s heat energy.

so the temp. of the room wil increase, but it will be filled with complete darkness.
 
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