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 solid angle subtended by an area of 2400 cm2 on the surface of a sphere of diameter 1.2 m is 3 / 2. 2 / 5. 1 / 3. 2 / 3. 3 / 2. 2 / 5. 1 / 3. 2 / 3. 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 5 6 4 2 5 6 4 ANSWER DOWNLOAD EXAMIANS APP
Illumination The illumination at a point 5 meters below a lamp in 6 lux. The candle power of the lamp is 30 200. 150. 140. 30 200. 150. 140. ANSWER DOWNLOAD EXAMIANS APP
Illumination Which among the following lamps has the maximum burning hours? Compact Fluorescent. LED. Incandescent. Metal halide. Compact Fluorescent. LED. Incandescent. Metal halide. ANSWER DOWNLOAD EXAMIANS APP
Illumination Candela/metre square is the unit of which photometric quantity? Luminous flux Luminous Intensity Luminance Illuminance Luminous flux Luminous Intensity Luminance Illuminance ANSWER DOWNLOAD EXAMIANS APP
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