Question

Classical mechanics, quantum mechanics, electromagnetic theory, solid state physics, nuclear physics , atomic physics, molecular physics, electronics, lasers, photonics, particle physics, etc.)

Answer 1

i didnt get your question

Answer 2

it's the physics that explains how everything works: the best description we have of the nature of the particles that make up matter and the forces with which they interact. Quantum physics underlies how atoms work, and so why chemistry and biology work as they do.