Box o' light?

For those of you who know more about this than me, please help me out.
Say you had a wooden box. Inside this wooden box there was a solid lining of mirrors. No creases, no holes, no cracks, etc. if you opened the box and placed a flashlight inside and closed it, when the flashlight ran out of batteries, would there still be light in the box. One would think the light would reflect off of the mirrors until the box was opened and allowed it to escape. Would this be an eternal box of light? I don’t know enough about light to conclude anything on this topic. What do you think?

The light would reflect many thousands of time but with each reflection it would loose some energy, and after a small amount of time (a millisecond ?) it would no longer be present. Light looses energy by absorbtion from the mirrors and by being slightly converted into heat.

There would only be darkness inside.

There is no perfectly reflecting material; every material has some nonzero chance of absorbing photons that hit it. Thus the light’s intensity will decrease exponentially, with the half-life depending on the absorbance of the mirrors. I expect that ordinary mirrors would absorb the light pretty quickly.

that makes a lot of sense. I guess a part of me wanted to believe the light would reflect forever, but I guess it is what it is. Thank you.

Hi your cousin,

You are not the only one to think that light would go on reflecting indefinitely. Honeywell when it first developed a ring laser for navigational purposes gave a lifetime guaranty, believing that the light would be absorbed and released in quanta, without any of the standard frictional forces being applicable.

I hope you enjoy your time posting here.

Ed