The one parameter that determines the brightness of a light source sensed by an eye is

The capability of the radiating source to produce total brightness is known as the total luminous flux. It is also defined as the total energy entering to our eyes that creates sensation of vision.


All the energy and wavelengths of light entering in eyes cannot be sensed by eyes. The radiation flux can be produced by all the wavelength of the light, which is not visible by eyes.


The one parameter that determines the brightness of a light source sensed by an eye is total luminous flux entering the eye.


So, option D is correct.

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