Illumination A 1000 W bulb fitted with a reflector illuminates an area of 3 m x 3 m with an average illumination of 450 lux. If the bulb has and efficiency of 9 lumens / watt the efficiency of the reflector is 30 %. 45 %. 20 %. 70 %. 30 %. 45 %. 20 %. 70 %. ANSWER DOWNLOAD EXAMIANS APP
Illumination The work of ballast in a fluorescent tube is to limit the flow of current. None of these. provide a kick start when voltage is induced. both ‘a’ and ‘b’. limit the flow of current. None of these. provide a kick start when voltage is induced. both ‘a’ and ‘b’. ANSWER DOWNLOAD EXAMIANS APP
Illumination What will be the total flux emitted by a source of 60 candle power? 0.001326 lumens. 754.2 lumens. 60 lumens. None of these. 0.001326 lumens. 754.2 lumens. 60 lumens. None of these. ANSWER DOWNLOAD EXAMIANS APP
Illumination What is the work of a driver in case of an LED? Both ‘a’ and ‘b’ To convert AC to DC None of these To convert DC to AC Both ‘a’ and ‘b’ To convert AC to DC None of these To convert DC to AC ANSWER DOWNLOAD EXAMIANS APP
Illumination The solid angle subtended by an area of 2400 cm2 on the surface of a sphere of diameter 1.2 m is 2 / 3. 2 / 5. 3 / 2. 1 / 3. 2 / 3. 2 / 5. 3 / 2. 1 / 3. ANSWER DOWNLOAD EXAMIANS APP
Illumination Which lamp has a negative Colour Rendering Index (CRI)? Low pressure sodium vapour High pressure sodium vapour Fluorescent LED Low pressure sodium vapour High pressure sodium vapour Fluorescent LED ANSWER DOWNLOAD EXAMIANS APP
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