Question

write the name of SI unit of luminous intensity​

Answer 1

candela

The SI unit of luminous intensity is the candela (cd). The lumen second is sometimes called the talbot. Luminous flux per unit solid angle per unit projected source area. The candela per square metre is sometimes called the nit.

The candela (cd) is defined by taking the fixed numerical value of the luminous efficacy of monochromatic radiation of frequency 540 × 1012 Hz, Kcd, to be 683 when expressed in the unit lm W−1, which is equal to cd sr W−1, or cd sr kg−1 m−2 s3, where the kilogram, meter and second are defined in terms of h, c and ∆νCs.