Why should you study physics? What is the use of a physics education? Do you still need to understand physics in case you aren't going to become a scientist? For the scientist (or aspiring scientist), the question of why to study science doesn't need to be answered.  No explanation is required in case you're one of the people who get science. Chances are that you already have at least some of the scientific skills necessary to pursue such a career, and the whole point of study is to gain the skills which you don't yet have. However, it can frequently feel as if science courses of any stripe are a waste of your time for those who are not pursuing a career in the sciences, or in technology. With courses in biology taking their place to fill necessary science requirements, courses in the physical sciences, especially, tend to be avoided at all cost. The argument in favor of "scientific literacy" is amply made in James Trefil's 2007 book Why Science that focuses on arguments from civics, aesthetics, and culture to explain why a very basic understanding of scientific concepts is necessary for the non-scientist. The benefits of a scientific education can be clearly seen in this description of science by famed quantum physicist Richard Feynman.

 

Why study physics

Science is a way to teach how something gets to be known, what is not known, to what extent things are known (for nothing is known absolutely), how to handle doubt and uncertainty, what the rules of evidence are, how to think about things so that judgments can be made, how to distinguish truth from fraud, and from show. The question then becomes (assuming you agree with the merits of the above way of thinking) how this form of scientific thinking can be imparted upon the population. Trefil refers to the "physics first" approach presented by 1988 Nobel Laureate Leon Lederman in his Chicago-based educational reforms. While he believes the more traditional biology first curriculum is appropriate for younger (elementary & middle school) students, his analysis is that this method is especially useful for older (i.e. high school age) students. This approach emphasizes the idea that physics is the most fundamental of sciences in short. Chemistry is applied physics, after all, and biology (in it's modern form, at least) is basically applied chemistry. You can of course extend beyond that into more specific fields ... zoology, ecology, & genetics are all further applications of biology, for example. But  in principle, the point is that all of science can be reduced down to fundamental physics concepts such as nuclear physics.  In fact, this is how physics developed historically: basic principles of physics were determined by Galileo while biology still consisted of various theories of spontaneous generation, after all. Because it is the foundation of science, gounding a scientific education in physics makes perfect sense. You can expand naturally into the more specialized applications, going from thermodynamics & nuclear physics into chemistry, for example, and from mechanics & material physics principles into engineering from physics.