Which cells in the eye are responsible for scotopic vision? Rod cells Both ‘a’ and ‘b’ None of these Cone cells TRUE ANSWER : ? YOUR ANSWER : ?
Which lamp has the best Colour Rendering Index (CRI)? Fluorescent Incandescent LED High pressure sodium vapour 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 45 %. 30 %. 70 %. 20 %. TRUE ANSWER : ? YOUR ANSWER : ?
Solid angle is expressed in terms of degree. radians. steredians. radians / meter. TRUE ANSWER : ? YOUR ANSWER : ?
Candela is the unit of which? Luminous intensity. Frequency. Luminous flux. Wavelength. TRUE ANSWER : ? YOUR ANSWER : ?
Candela/metre square is the unit of which photometric quantity? Luminous Intensity Illuminance Luminous flux Luminance TRUE ANSWER : ? YOUR ANSWER : ?
Which lamp is best suited for lighting an International sports arena? Metal Halide Incandescent Compact Fluorescent LED TRUE ANSWER : ? YOUR ANSWER : ?
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’. TRUE ANSWER : ? YOUR ANSWER : ?
Luminous efficacy of a typical HPSV lamp is in between 40 - 70 lm/watt. 70 - 120 lm/watt. 120 - 200 lm/watt. 10 - 40 lm/watt TRUE ANSWER : ? YOUR ANSWER : ?
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. 17.32 lux. 1.15 lux. 58.45 Kilolux. TRUE ANSWER : ? YOUR ANSWER : ?