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This equation is known as the Planck relation. Additionally, using equation f = c/λ, = where E is the photon's energy; λ is the photon's wavelength; c is the speed of light in vacuum; h is the Planck constant; The photon energy at 1 Hz is equal to 6.626 070 15 × 10 −34 J, which is equal to 4.135 667 697 × 10 −15 eV.
Factor by which the phase velocity of light is reduced in a medium unitless 1: intensive, scalar Reluctance: resistance to the flow of magnetic flux H −1: L −2 M −1 T 2 I 2: scalar Solid angle: Ω: Ratio of area on a sphere to its radius squared steradian (sr) ∠ 2: Specific energy: Energy density per unit mass
The light-second is a unit of length useful in astronomy, telecommunications and relativistic physics. It is defined as the distance that light travels in free space in one second , and is equal to exactly 299 792 458 m (approximately 983 571 055 ft or 186 282 miles ).
Photons are massless particles of definite energy, definite momentum, and definite spin. To explain the photoelectric effect, Albert Einstein assumed heuristically in 1905 that an electromagnetic field consists of particles of energy of amount hν, where h is the Planck constant and ν is the wave frequency.
One example is represented by the conditions in the first 10 −43 seconds of our universe after the Big Bang, approximately 13.8 billion years ago. The four universal constants that, by definition, have a numeric value 1 when expressed in these units are: c, the speed of light in vacuum, G, the gravitational constant, ħ, the reduced Planck ...
Visible light is an electromagnetic wave, consisting of oscillating electric and magnetic fields traveling through space. The frequency of the wave determines its color: 400 THz (4 × 10 14 Hz) is red light, 800 THz (8 × 10 14 Hz) is violet light, and between these (in the range 400–800 THz) are all the other colors of the visible spectrum.
The speed of light in vacuum, commonly denoted c, is a universal physical constant that is exactly equal to 299,792,458 metres per second (approximately 300,000 kilometres per second; 186,000 miles per second; 671 million miles per hour).
The template will not display the string "Table X. " in front of the table's title "SI photometry units". 1 = <number> The template will display the table number as part of the table header in the following form: "Table <number>. SI photometry units.", where <number> is a placeholder for the number (or other table designation) given as parameter.