Physics seeks to discover the most basic laws of the universe; it tries to explain why things are the way they are at the most fundamental level. It is the foundation upon which the other physical sciences - astronomy, chemistry, geology - are based. How did our universe originate? What are things made up of at the smallest level? What is space? What is time? How do things move and why? Why is ice a solid, but water is not?... Those are the sorts of questions physics attempts to answer within the framework of its theories.
An understanding of physics is essential for engineering and technology. The design of heat engines, vehicles, electrical devices from power generators to microwave ovens to computers, is best done after gaining a solid grounding in physics. Every undergraduate engineering program requires at least two semesters of physics. Biology and medicine use several ideas and tools of physics, e.g., force, pressure, energy, acoustics, optics, electronics, X rays, and radiation. Most undergraduate biology and health sciences programs require two semesters of physics.