Illumination A 200 candle power lamp is hung 4 m above the centre of circular area of 5 m diameter. The illumination at centre of the area is 17.5 lux. 12.5 lux. 18.5 lux. 13.5 lux. 17.5 lux. 12.5 lux. 18.5 lux. 13.5 lux. ANSWER DOWNLOAD EXAMIANS APP
Illumination The illumination of the surface varies directly with cosine of the angle between normal to surface and direction of the inclined light is given by Lambert’s cosine law. both A and B. None of these law of square inverse. Lambert’s cosine law. both A and B. None of these law of square inverse. ANSWER DOWNLOAD EXAMIANS APP
Illumination In illumination technology total lumens emitted by source / total lumens available after waste of light is equal to beam factor. absorption factor. utilization factor. waste light factor. beam factor. absorption factor. utilization factor. waste light factor. ANSWER DOWNLOAD EXAMIANS APP
Illumination Luminous efficiency of a fluorescence lamp is 40 lumens / watt. 60 lumens / watt. 30 lumens / watt. 70 lumens / watt. 40 lumens / watt. 60 lumens / watt. 30 lumens / watt. 70 lumens / watt. ANSWER DOWNLOAD EXAMIANS APP
Illumination What will be the total flux emitted by a source of 60 candle power? 60 lumens. 0.001326 lumens. None of these. 754.2 lumens. 60 lumens. 0.001326 lumens. None of these. 754.2 lumens. ANSWER DOWNLOAD EXAMIANS APP
Illumination What is the ratio of illuminance at a point 5m just below a lamp emitting 100 candelas and at a point 5m away from the first point on the same horizontal plane? 2:1 2√2 : 1 1: 2√2 1:2 2:1 2√2 : 1 1: 2√2 1:2 ANSWER DOWNLOAD EXAMIANS APP
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