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 law of square inverse. None of these Lambert’s cosine law. both A and B. law of square inverse. None of these Lambert’s cosine law. both A and B. 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 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√2 : 1 2:1 1: 2√2 1:2 2√2 : 1 2:1 1: 2√2 ANSWER DOWNLOAD EXAMIANS APP
Illumination Illumination can be expressed in lumens. lux. radians. candela. lumens. lux. radians. candela. ANSWER DOWNLOAD EXAMIANS APP
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 20 %. 45 %. 70 %. 30 %. 20 %. 45 %. 70 %. 30 %. 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