Unpolarized light of intensity is incident on a linear polarizer. The transmitted light then passes through a second polarizer (analyzer) whose transmission axis is oriented at an angle of relative to the first polarizer. What is the final transmitted intensity?

Answer and explanation

Correct answer: B.

  1. Step 1: When unpolarized light passes through the first ideal polarizer, its intensity is halved: .
  2. Step 2: According to Malus's law, when polarized light passes through the analyzer, the transmitted intensity is .
  3. Step 3: Substitute : . Compute: .
Answer
.
Why not the others: is the intensity after the first polarizer; omits the initial unpolarized halving factor; uses .

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