The solid angle subtended by an area of 2400 cm2 on the surface of a sphere of diameter 1.2 m is 1 / 3. 3 / 2. 2 / 5. 2 / 3. TRUE ANSWER : ? YOUR ANSWER : ?
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 %. 30 %. 70 %. 45 %. TRUE ANSWER : ? YOUR ANSWER : ?
The illumination at a point 5 meters below a lamp in 6 lux. The candle power of the lamp is 140. 30 150. 200. TRUE ANSWER : ? YOUR ANSWER : ?
___________________________ factor is defined as the ratio of the illumination when everything is clean to illumination under normal working conditions. Utilization. Maintenance. Depreciation. Absorption factor. TRUE ANSWER : ? YOUR ANSWER : ?
The work of ballast in a fluorescent tube is to None of these. provide a kick start when voltage is induced. limit the flow of current. both ‘a’ and ‘b’. TRUE ANSWER : ? YOUR ANSWER : ?
Which lamps can be directly connected to a solar cell? Compact Fluorescent Incandescent LED Metal Halide TRUE ANSWER : ? YOUR ANSWER : ?
What will be the total flux emitted by a source of 60 candle power? None of these. 754.2 lumens. 0.001326 lumens. 60 lumens. TRUE ANSWER : ? YOUR ANSWER : ?
Which lamp has the best Colour Rendering Index (CRI)? Fluorescent High pressure sodium vapour LED Incandescent TRUE ANSWER : ? YOUR ANSWER : ?
Solid angle is expressed in terms of radians. radians / meter. steredians. degree. TRUE ANSWER : ? YOUR ANSWER : ?