Illumination Luminous efficacy of a typical HPSV lamp is in between 10 - 40 lm/watt 120 - 200 lm/watt. 40 - 70 lm/watt. 70 - 120 lm/watt. 10 - 40 lm/watt 120 - 200 lm/watt. 40 - 70 lm/watt. 70 - 120 lm/watt. ANSWER DOWNLOAD EXAMIANS APP
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 18.5 lux. 12.5 lux. 13.5 lux. 17.5 lux. 18.5 lux. 12.5 lux. 13.5 lux. 17.5 lux. ANSWER DOWNLOAD EXAMIANS APP
Illumination In illumination technology total lumens emitted by source / total lumens available after waste of light is equal to utilization factor. beam factor. waste light factor. absorption factor. utilization factor. beam factor. waste light factor. absorption factor. ANSWER DOWNLOAD EXAMIANS APP
Illumination What is the work of a driver in case of an LED? Both ‘a’ and ‘b’ None of these To convert DC to AC To convert AC to DC Both ‘a’ and ‘b’ None of these To convert DC to AC To convert AC to DC ANSWER DOWNLOAD EXAMIANS APP
Illumination Wave length for red colour is around 700 nm. 600 nm. 500 nm. 400 nm. 700 nm. 600 nm. 500 nm. 400 nm. 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? 1: 2√2 1:2 2√2 : 1 2:1 1: 2√2 1:2 2√2 : 1 2:1 ANSWER DOWNLOAD EXAMIANS APP