How would a knowledge of physical science be useful to a photographer?

Photoshop

I would venture to you that all knowledge makes us better at what we do.

Physical science is the study of physics, chemistry, astronomy, and geology.

- In lighting, it's helpful to understand the amplitude of the lights and how it effects their life span (those bulbs cost a fortune.)
- The temperature they radiate effects the color tone and ambiance of your photograph and will directly translate into what F-stop you should use.
- Astronomy is in small part a study of atmospherics and how light and air effect what we see. When in Photoshop, it will be important to replicate these effects flawlessly to make it seem as if you captured them yourself.
- The chemical composition of rocks and your ability to identify them could help you find a natural 'bounce' when shooting in rocky terrain.

he can know exactly what amount of light is needed at which particular place.