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प्रश्न
As the wavelength is increased from violet to red, the luminosity ____________ .
पर्याय
continuously increases
continuously decreases
increases then decreases
decreases then increases
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उत्तर
increases then decreases
The luminosity first increases up to 555 nm and then decreases.
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Mark the correct options.
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(b) The luminous efficiency of a monochromatic source of wavelength 555 nm is always greater than that of a white light source of same power.
(c) The illuminating power of a monochromatic source of wavelength 555 nm is always greater than that of a white light source of same power.
(d) The illuminating power of a monochromatic source is always greater than that of a white light source of same power.
Mark out the correct options.
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(d) Relative luminosity is a dimensionless quantity.
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