# How bright?

1. Nov 25, 2004

### vikasj007

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?

2. Nov 25, 2004

### DaveC426913

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.

3. Nov 26, 2004

### Moonbear

Staff Emeritus
Sounds like standing on the inside of an Easy Bake Oven, doesn't it?

4. Nov 27, 2004

### vikasj007

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.

5. Nov 27, 2004

### Physics is Phun

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)

6. Dec 3, 2004

### Dual Op Amp

They would be just as bright as the bulb emmitting the light.

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

They would be the color of the light emitting, white.

Last edited: Dec 3, 2004
7. Dec 4, 2004

### vikasj007

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.