How Everything Works
How Everything Works How Everything Works

Question 349

What is black light and how does it work?
Black light is ultraviolet light. You cannot see it so a room illuminated only by ultraviolet light appears dark or "black". However any fluorescent materials in the room (e.g. brighteners in your clothes) will absorb the ultraviolet light and reemit it as visible light. That is why things with fluorescent pigments on them glow when illuminate by black light.

Copyright 1997-2017 © Louis A. Bloomfield, All Rights Reserved
Privacy Policy