By Surendra | June 11, 2020 0 Comment 0% 3 Created by Surendra Electric Illumination Quiz in English Set 1 All Important Question Answers for Electrician Related Exams 1 / 20 Luminous efficiency of a fluorescent tube is 15-20 lumens/watt 30 - 40 lumens/watt 60 - 65 lumens/watt. 5- 10 lumens/watt 2 / 20 The unit of luminous flux is lumen candela steradian lux. 3 / 20 Radiant efficiency of the luminous source depends on temperature of the source all of the above. wavelength of light rays shape of the source 4 / 20 Light is produced in electric discharge lamps by ionization in a gas or vapor heating effect of current magnetic effect of current carbon electrodes. 5 / 20 Illumination level required for precision work is around 500 lm/m2. 200 lm/m2 50 lm/m2 100 lm/m2 6 / 20 Candela is-the unit for Brightness Light flux Luminous intensity Luminous efficiency. 7 / 20 Which of the following will need the highest level of illumination ? Railway platforms. Bed rooms Proof reading Hospital wards 8 / 20 Melting temperature of tungsten is 3655°K. 2000°K 2500°K 2655°K 9 / 20 The illumination level in houses is in the range 30 - 50 lumen/m2 40-75 lumen/m2 100-140 lumen/m2. 10-20 lumen/m2 10 / 20 Which photometer depends for its operation on Inverse Square Law ? Trotter Illumination Photometer. Lummer Brodhun Photometer Guilds Flicker Photometer Macbeth illuminometer 11 / 20 Candela is the unit of Wavelength Luminous flux Luminous intensity None of the above. 12 / 20 Which of the following lamp gives nearly monochromatic light ? Mercury vapor lamp. Sodium vapor lamp GLS lamp Tube light 13 / 20 Carbon arc lamps are commonly used in photography. domestic lighting cinema projectors street lighting 14 / 20 Lumen/watt is the unit of Brightness Luminous intensity Light flux Luminous efficiency. 15 / 20 The unit of solid angle is solid angle radian candela. steradian 16 / 20 The illumination is directly proportional to the cosine of the angle made by the normal to the illuminated surface with the direction of the incident flux. Above statement is associated with Macbeth's law of illumination Bunsen's law of illumination Planck's law Lambert's cosine law. 17 / 20 The color temperature of day light is around 600 K 50 K 160 K 6000 K. 18 / 20 Which of the following will need lowest level of illumination ? Auditoriums. Displays Fine engraving Railway platform 19 / 20 Light waves travel with a velocity of 3 x 1018 cm/s. 3 x 1010cm/s 3 x 1015 cm/s 3 x 1012cm/s 20 / 20 One lumen per square meter is the same as One lux One lumen meter. One foot candle One candela कृपया सही सूचना भरें ताकि सर्टिफिकेट ईमेल पर भेजा जा सकें। NameEmailPhone NumberDistrictSchool/Coaching Name Your score is LinkedIn Facebook VKontakte 0% Restart quiz आपको यह क्विज अच्छी लगी तो 5 स्टार रेटिंग जरुर दें । Send feedback
