Define the following terms and state their units: (i) Luminous intensity, (ii) Luminous flux

1 Answer

Answer :

i) Luminous intensity: This is defined as the luminous flux emitted into a solid angle of space in a specific direction. Its unit is the candela. 

OR 

The luminous flux per unit solid angle (per steradian), as measured in a given direction relative to a light source. Its unit is the candela.


ii) Luminous Flux: The luminous flux is the total energy radiated by the light source in all direction. The unit of luminous flux is lumen (lm) 

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