Theoretical 100% Light Reflection Room

[doanr]

If there was a room with all walls that are 100% reflective and a light source. If you were to instantaneously remove that light source, would the room still be lighted?
If yes, if an object and the light source were previously present the room, and were to be instantaneously removed, would the room be reflecting scattered images of that object?
If yes, if we were capable of completely absorbing the remaining photons, can we potentially decipher what the object was?
Again if so, can this ever be used in a real life situation, like solve a crime scene by using remaining photon in the room?
(Sorry if I am not using the correct terms; Amateur hour over here and I'm just really curious about this.)

 

[mfb]

If there was a room with all walls that are 100% reflective and a light source. If you were to instantaneously remove that light source, would the room still be lighted?

If there is nothing inside that is not 100% reflective, the light would stay inside. If you want to call that "lighted"... well, a question of definition.

If yes, if an object and the light source were previously present the room, and were to be instantaneously removed, would the room be reflecting scattered images of that object?

It would become unrecognizable in microseconds due to all the reflections.

Again if so, can this ever be used in a real life situation, like solve a crime scene by using remaining photon in the room?

We don't have 100% reflective rooms. The light vanishs within less than a microsecond.