Question

Light from a source is analysed by an analyser. When the analyser is rotated, the intensity of the emergent light.

• A. Does not vary
• B. Remains uniformly dark
• C. Varies between maximum and zero
• D. Varies between maximum and minimum

Answer 1

The correct option is A Does not vary

Let the intensity of the unpolarised light be $I_o$.
An analyser is used to polarized the light in one direction.
Intensity of light after passing through the analyser $I^{\prime }=\frac{I_o}{2}$
Intensity of light after passing through analyser remains constant $I_o/2$ even if the analyser is rotated by some angle.