Overview
Physics studies physical systems from subatomic particles to galaxies. Mechanics examines motion and forces; thermodynamics concerns heat and energy transfer; electromagnetism addresses electric and magnetic phenomena. Quantum theory and relativity extend understanding beyond everyday scales. Across these areas, physicists seek models that explain observations and make predictions that can be compared with measurements.
Core ideas
Conservation of energy and momentum provides powerful constraints on change. Forces influence acceleration rather than simply sustaining motion. Models often begin with idealizations, such as negligible friction, whose usefulness depends on context. Units, dimensional analysis, uncertainty, and significant figures help distinguish meaningful results from numbers that appear more precise than the evidence permits.
Try it
Time a pendulum made from a lightweight object on a string, using small swings and a secure attachment. Measure several oscillations together and compare different string lengths. Repeat trials and plot period against length. Explain how timing error and swing size affect your results, keeping the object away from faces, fragile items, and crowded areas.
Study pathways
Further study supports engineering, astronomy, instrumentation, medical physics, computing, and research. Mathematics and experimental recordkeeping are essential foundations. Clinical medical physics and safety-critical engineering require specialized professional preparation beyond introductory physics. Learn electrical, radiation, laser, and mechanical safety before advanced experiments; familiar-looking equipment can still create hazards that are not obvious from appearance alone.