Question

Different between sodium vapour lamp and incandescent lamp

Answer 1

Answer:

Light Source

Sodium vapour lamp:Works by electric discharge (passage of electricity through sodium vapours at high/low pressure)

inacandesent lamp :Works through the combined effect of electric discharge through mercury vapours and fluorescence from phosphors (luminescent materials).

Applications

sodium vapour lamp :Although sodium vapour lamps produce much higher light output (about 90 lumens/watt) they cannot be used in lighting applications where colour-rendering property is very crucial. This is because most of the light emitted from a sodium vapour lamp is concentrated in the yellow part of the visible spectrum (around 580-590 nm).

inacandesent lamp: Mercury vapour lamp is quite suitable for lighting applications. This is because, the mercury vapour lamp can feed almost the entire visible region (380-780 nm) of the human visual system