photometry

IIT JEE 2015 Answers › Optics questions › photometry

1)why is luminous efficiency small for a filament bulb as compared to a mercury varour lamp?
2)the yellow colour has greater luminous efficieny as compared to the other colours Can we increase the illuminating power of a white light source by putting a yellow plastic paper around this source

#Physics #Optics

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3 Answers

11

virang1 Jhaveri ·2009-03-21 04:37:59

1)
In a filament bulb the energy is first used to heat the filament to a high temperature wasting the energy while the mercury vapour using lesser energy to give out light therefore the efficeny is better

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24

eureka123 ·2009-03-21 11:01:47

i think photometry is not in syllabus........[251]

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tapanmast Vora ·2009-03-21 11:14:12

potometry = [48]

NAHI HAI BHAI [49]

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Your Answer

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