Illumination Candela/metre square is the unit of which photometric quantity? Luminous Intensity Illuminance Luminance Luminous flux Luminous Intensity Illuminance Luminance Luminous flux ANSWER DOWNLOAD EXAMIANS APP
Illumination From a uniform light source having luminous intensity of 300 candelas, there exists a plane surface 15 m below. The value of illuminance at a point on the plane surface where the luminous flux rays are inclined at an angle of 30 to the surface is 1.53 lux. 58.45 Kilolux. 1.15 lux. 17.32 lux. 1.53 lux. 58.45 Kilolux. 1.15 lux. 17.32 lux. 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 To convert DC to AC None of these Both ‘a’ and ‘b’ To convert AC to DC To convert DC to AC None of these 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. None of these both A and B. law of square inverse. Lambert’s cosine law. None of these both A and B. law of square inverse. ANSWER DOWNLOAD EXAMIANS APP
Illumination What will be the number of lamps, each having 300 lumens, required to obtain an average illuminance of 50 lux on a 4m × 3m rectangular room? 2 4 6 5 2 4 6 5 ANSWER DOWNLOAD EXAMIANS APP
Illumination The work of ballast in a fluorescent tube is to None of these. both ‘a’ and ‘b’. provide a kick start when voltage is induced. limit the flow of current. None of these. both ‘a’ and ‘b’. provide a kick start when voltage is induced. limit the flow of current. ANSWER DOWNLOAD EXAMIANS APP
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