The most non-polluting and efficient lighting device is :
(a) CFL (b) LED
(c) Fluorescent light (d) Electric bulb.
The most non-polluting and efficient lighting device is the LED.
Which of the following device is most efficient for the lighting purpose :
LED, CFL, Fluorescent tube light, Electric bulb.
In a filament type light bulb, most of the electric power consumed appears as: (a) visible light (b) infra - red - rays (c) ultravioley rays (d) fluorescent light