Search results
Results from the WOW.Com Content Network
The study of light, known as optics, is an important research area in modern physics. The main source of natural light on Earth is the Sun . Historically, another important source of light for humans has been fire , from ancient campfires to modern kerosene lamps .
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. [1] Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Light is a type of electromagnetic radiation, and other forms of ...
The phase velocity is important in determining how a light wave travels through a material or from one material to another. It is often represented in terms of a refractive index. The refractive index of a material is defined as the ratio of c to the phase velocity v p in the material: larger indices of refraction indicate lower speeds.
History of optics. Modern ophthalmic lens making machine. Optics began with the development of lenses by the ancient Egyptians and Mesopotamians, followed by theories on light and vision developed by ancient Greek philosophers, and the development of geometrical optics in the Greco-Roman world. The word optics is derived from the Greek term ...
James Clerk Maxwell. James Clerk Maxwell FRS FRSE (13 June 1831 – 5 November 1879) was a Scottish physicist with broad interests [ 1 ][ 2 ] who was responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism and light as different manifestations of the same phenomenon.
Condensed. I (J P C)=0,1 (1 −−) [ 1 ] A photon (from Ancient Greek φῶς, φωτός (phôs, phōtós) 'light') is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force.
A ray of light being refracted through a glass slab. In optics, the refractive index (or refraction index) of an optical medium is a dimensionless number that gives the indication of the light bending ability of that medium. Refraction of a light ray. The refractive index determines how much the path of light is bent, or refracted, when ...
1. First postulate (principle of relativity) The laws of physics take the same form in all inertial frames of reference. 2. Second postulate (invariance of c) As measured in any inertial frame of reference, light is always propagated in empty space with a definite velocity c that is independent of the state of motion of the emitting body.