Which of the following is the SI unit of luminous intensity?
A
Sterdian
B
Radian
C
Mole
D
Candela
Correct Answer: Candela
Candela is the SI unit of luminous intensity. One candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540×1012 hertz and that has a radiant intensity of 1/683 watt per sterdian in that direction.