Unpolarized light of intensity passes through an ideal polarizer A. Another identical polarizer B is placed behind A. The intensity of light beyond B is found to be . Now another identical polarizer C is placed between A and B. The intensity beyond B is now found to be . The angle between polarizer A and C is:
Step 1: Given
The initial intensity of light:
The intensity of light after A:
The intensity of light after B:
The intensity of light after B when C is also placed:
Step 2: Formula Used
Malus Law Formula:
Step 3: Find the angle between A and C
When light passes through a polariser its intensity becomes half. Here, when the light passes through A its intensity becomes half and again when it passes through B its intensity remains same as after passing through A. This implies that A and B are parallel to each other. Now, find an expression after light passes through C using Malus law.
Calculate the value of angle using Malus law and substituting values
Hence, the angle between polariser A and C is .