Search results
Results from the WOW.Com Content Network
Ultraviolet (UV) light is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs, Cherenkov radiation, and ...
At the same time, light is intrinsically found in painting, since it is indispensable for the composition of the image: the play of light and shadow is the basis of drawing and, in its interaction with color, is the primordial aspect of painting, with a direct influence on factors such as modeling and relief. [ 1 ]
Luminous efficacy is a measure of how well a light source produces visible light. It is the ratio of luminous flux to power, measured in lumens per watt in the International System of Units (SI). Depending on context, the power can be either the radiant flux of the source's output, or it can be the total power (electric power, chemical energy ...
A solar cell or photovoltaic cell (PV cell) is an electronic device that converts the energy of light directly into electricity by means of the photovoltaic effect. [ 1 ] It is a form of photoelectric cell, a device whose electrical characteristics (such as current, voltage, or resistance) vary when it is exposed to light.
Quantum dots (QDs) or semiconductor nanocrystals are semiconductor particles a few nanometres in size with optical and electronic properties that differ from those of larger particles via quantum mechanical effects. They are a central topic in nanotechnology and materials science.
An electron in an atom can absorb energy from light or heat only if there is a transition between energy levels that match the energy carried by the photon or phonon. For light, this means that any given transition will only absorb one particular wavelength of light. Photons with the correct wavelength can cause an electron to jump from the ...
Plasmas are studied by the vast academic field of plasma science or plasma physics, including several sub-disciplines such as space plasma physics. Plasmas can appear in nature in various forms and locations, with a few examples given in the following table: Common forms of plasma. Artificially produced.
A sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm. Two varieties of such lamps exist: low pressure and high pressure. Low-pressure sodium lamps are highly efficient electrical light sources, but their yellow light restricts applications to outdoor ...