A) Osmium B) Tantalum C) Tungsten D) Carbon. Ans : (A)
A) 0.5 leading B) unity C) 0.5 lagging D) 0.8 lagging. Ans : (B)
A) changes the colour of light B) acts as a shield around the filament C) prevents vaporization of filaments D) assists in developing enough heat to vaporize the sodium. Ans : (D)
A) Neon lamp B) Low pressure mercury vapour lamp C) High pressure mercury vapour lamp D) Sodium vapour lamp. Ans : (A)
A) Converts visible light into ultra-violet radiations B) Converts ultra-violet radiations into visible light C) Reduces glare D) None of the above. Ans : (B)
A) Sports grounds B) Parks C) Airports D) All of the above. Ans : (D)
A) Sodium vapour lamp B) GLS lamp C) Tube light D) Mercury vapour lamp. Ans : (A)
A) transparent B) white C) opaque D) green to red. Ans : (B)
A) no depreciation of light output B) increased operating temperature with increased luminous efficiency C) reduced dimensions of the lamp D) all of the above. Ans : (D)
A) Lumen output B) Power consumption C) Life D) Efficiency. Ans : (C)