Concepts Of Physics MCQ Edition [Volume 1]PhysicsPhotometry
Select the correct options from the following.
Options
- ARelative luminosity is a quantity without dimensions.
- BRadiant flux and power possess identical dimensions.
- CLuminous flux and radiant flux possess identical dimensions.
- DLuminous flux and luminous intensity possess identical dimensions.
Correct answer
D. Luminous flux and luminous intensity possess identical dimensions.
Step-by-step solution
Relative luminosity is defined as the ratio of the luminosity of a particular wavelength to the maximum luminosity. Being a ratio of two identical quantities, it is a dimensionless quantity. Radiant flux is the total radiant energy emitted per unit time. Its unit is Watt, which is the same as that of power. Thus, radiant flux and power have identical dimensions of [M L^2 T⁻³] . Luminous flux is measured in lumens, where 1 lumen = 1 candela 1 steradian . Since solid angle (steradian) is a dimensionless quantity, lum