Based on observations and analysis, they attempt to discover the laws that describe the forces of nature, such as gravity, electromagnetism, and nuclear interactions. They also find ways to apply physical laws and theories to problems in nuclear energy, electronics, optics, materials, communications, aerospace technology, and medical instrumentation. However, all physics involves the same fundamental principles, specialties may overlap, and physicists may switch from one subfield to another. Also, large numbers of physicists work in interdisciplinary fields such as biophysics, chemical physics, geophysics, meteorology, oceanography, and seismology. Research and development work is an integral part of most physicists' jobs.
Some physicists work exclusively in research and development.
Some do basic research to increase scientific knowledge. For example, they investigate the structure of the atom or the nature of gravity. Physicists who conduct applied research build upon the discoveries made through basic research and work to develop new devices, products and processes. For instance, basic research in solid-state physics led to the development of transistors and then to the integrated circuits used in computers. Physicists also design research equipment.