+What is Physics?

What is Physics?

Physics is a natural science based on experiments, measurements and mathematical analysis with the purpose of finding quantitative physical laws for everything from the nanoworld of the microcosmos to the planets, solar systems and galaxies that occupy the macrocosmos.

The laws of nature can be used to predict the behaviour of the world and all kinds of machinery. Many of the everyday technological inventions that we now take for granted resulted from discoveries in physics. The basic laws in physics are universal, but physics in our time is such a vast field that many subfields are almost regarded as separate sciences.

The early Greeks established the first quantitative physical laws, such as Archimedes' descriptions of the principle of levers and the buoyancy of bodies in water. But they did not actually conduct experiments, and physics as science stagnated for many centuries. By the 17th century, however, Galileo Galilei and later Issac Newton helped pioneer the use of mathematics as a fundamental tool in physics, which led to advances in describing the motion of heavenly bodies, the laws of gravity and the three laws of motion.

The laws of electricity, magnetism and electromechanical waves were developed in the 1800s by Faraday and Maxwell, in particular, while many others contributed to our understanding of optics and thermodynamics.

Modern physics can be said to have started around the turn of the 20th century, with the discovery of X-rays (Röntgen 1895), radioactivity (Becquerel 1896), the quantum hypothesis (Planck 1900), relativity (Einstein 1905) and atomic theory (Bohr 1913).

Quantum mechanics (Heisenberg and Schrödinger), beginning in 1926, also gave scientists a better understanding of chemistry and solid state physics, which in turn has led to new materials and better electronic and optical components. Nuclear and elementary particle physics have become important fields, and particle physics is now the basis for astrophysics and cosmology.

PHYSICS IN EVERYDAY LIFE

The most basic of the sciences, physics, is all around us every day. If you've ever wondered what makes lightning, why a boomerang returns, how ice skaters can spin so fast, how Michael Jordan can "fly," why waves crash on the beach, how that tiny computer can do complicated problems, or how long it takes light from a star to reach us, you have been thinking about some of the same things physicists study every day. Physicists like to ask questions. They try to find answers for almost everything_from when the universe began to why soda fizzes. If you like to explore and figure out why things are the way they are, you might like physics.
	If you've had a back-row seat at a rock concert, and could still hear, you experienced physics at work! Physicists studying sound contribute to the design of concert halls and the amplification equipment. Knowing more about how things move and interact can be used to manage the flow of traffic and help cities avoid grid lock.
	Ford driver Robby Gordon competing in the ITT Automotive Detroit Grand Prix. Aerodynamic engineering helps reduce drag and increase traction. (Photo courtesy Ford Motor Company/Campbell and Co.) PHYSICISTS AT WORK Research physicists work in industry and government, in laboratories and hospitals, and on university campuses. Some physicists serve in the military, teach in high schools and colleges, design science museum exhibits, write books and news articles about science, give advice to federal, state, local, and foreign governments, run businesses, even become artists. Students not interested in pursuing a science career can still benefit from courses in physics. The study of physics helps you acquire very special problem-solving skills and teaches you to better observe and understand the world. We all employ physical concepts in everyday life. NASA astronauts in weightless spaceflight conditions. The weightless conditions of spaceflight can be simulated by flying an airplane in a special arc. (Photo courtesy NASA.)