Laws of Motion — Physics STD 11 Science — Question

Mark the correct options.

1. The luminous efficiency of a monochromatic source is always greater than that of a white light source of same power.
2. The luminous efficiency of a monochromatic source of wavelength 555nm is always greater than that of a white light source of same power.
3. The illuminating power of a monochromatic source of wavelength 555nm is always greater than that of a white light source of same power.
4. The illuminating power of a monochromatic source is always greater than that of a white light source of same power.

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