All You Engineers Out There, How Often do you Use all that Calculus and Physics you worked so hard learning?

Quite a bit actually but a lot of it is buried in the software now. I've been working in R&D lately. Figuring out how to make perfect mirrors. Turns out it's not too hard so long as you have ion beam assited deposition and some tantalum oxide laying around. Oh, and at high wavelengths gold is really no better than aluminum (Sorry JST). It's 64 times more expensive so you're better off just applying 500 nm of aluminum. So, the understanding of materials and their interaction with force, heat, magnetism, and light are just as , and maybe more important as/ than the tools of physics and calculus.