Plane-polarized light of intensity 80 W/m^2 passes through two filters. The first is at 30^circ to the light's plane and the second at 30^circ to the first. The final intensity is:

  1. 60 W/m^2
  2. 47 W/m^2
  3. 20 W/m^2
  4. 45 W/m^2
Answer

D) 45 W/m^2

After the first: 80cos^2 30^circ = 60; after the second: 60cos^2 30^circ = 45 W/m^2. SLO P-11-D-06 · Understanding

Physics MCQ · More Polarization MCQs · Practise