Table 1. SI photometry units
Quantity Symbol[nb 1] SI unit Symbol Dimension Notes Luminous energy Qv [nb 2] lumen secondlm⋅s T⋅J [nb 3] units are sometimes called talbots Luminous flux Φv [nb 2] lumen (= cd⋅sr) lm J also called luminous power Luminous intensity Iv candela (= lm/sr) cd J an SI base unit, luminous flux per unit solid angle LuminanceLv candela per square metre cd/m2 L−2⋅J units are sometimes called nitsIlluminanceEv lux (= lm/m2) lxL−2⋅J used for light incident on a surface Luminous emittance Mv lux (= lm/m2) lx L−2⋅J used for light emitted from a surface Luminous exposure Hv lux secondlx⋅s L−2⋅T⋅J Luminous energy density ωv lumen second per metre3 lm⋅⋅m−3 L−3⋅T⋅J Luminous efficacy η [nb 2] lumen per wattlm/WM−1⋅L−2⋅T3⋅J ratio of luminous flux to radiant flux Luminous efficiency V 1 also called luminous coefficient
The SI unit of luminous intensity is the candela.
Luminous intensity is a scalar quantity, as it only has magnitude (brightness) and no direction associated with it. It is typically measured in units of candela.
Luminous intensity of a light is measured in candelas (cd). A device called a photometer is commonly used to measure the amount of light emitted by a source in a specific direction.
To calculate illuminance (lux) on a surface due to a point light source, you can use the formula: illuminance = luminous intensity / (distance)^2. Plugging in the values given (luminous intensity of 72 cd and distance of 3m), the illuminance on the surface would be 8 lux.
Not sure what formula you are looking for. Wave intensity is given by the amplitude of the wave.
Luxmeter measures luminous intensity. The SI unit of luminous intensity is candela (cd).
Any formula relating those two quantities must depend on the technique used to generate light by means of electric current. We know that there can't be one universal formula because, for example, we know that a compact fluorescent lamp uses less current to produce more luminous intensity than an incandescent lamp.
In the SI the unit of luminous intensity is candela(cd).
candela
The symbol for luminous intensity is Iv, and it is measured in candelas (cd) in the field of optics.
The SI unit of Intensity of light is CANDELA.
Lumens (Iv) oand/or candelas per square meter.
The SI unit of luminous intensity is the candela.
stilb(sb)
The SI unit for luminous intensity is candela (cd).
Luminous intensity is a scalar quantity, as it only has magnitude (brightness) and no direction associated with it. It is typically measured in units of candela.
It is luminous intensity measured in candelas