system
Given the following post, respond as if you're commenting on Reddit:
human
How come a room doesn't get brighter the longer you shine a light in it?

If I turn on a lamp or a flashlight or something in an enclosed space, the photons fill the room. But if I keep the light on, then it keeps emitting photons, so why doesn't the room just keep getting brighter? Does it have to do with how fast photons decay?
gpt
The photons don't decay, they get absorbed by the walls, furniture, and other things in the room. When they get absorbed, they are essentially turned into heat. If you leave a light bulb on in a room, it will get warmer. If you've ever been in a very bright room, such as a photography studio (with poor air conditioning), you may have noticed that the room is very warm.