HSC Physics Polarisation

A tutorial sheet of polarisation problems is given below

  1. When is a beam of light polarised?
  2. A beam of unpolarised light of intensity 4000 Wm-2 strikes a polarising filter. What is the transmitted intensity?
  3. Unpolarised light of intensity I passes through three polarising filters placed in a line. The polarising directions of the filters are are inclined at 45° to each other. Determine the intensity transmitted by the third filter.
  4. Polarised light of intensity I passes through three polarising filters placed in a line. The angle between the plane of polaristion of the light and the polarising direction of the first filter is 45°. If the polarising directions of the filters are inclined at 45° to each other, determine the intensity transmitted by the third filter.
  5. Light is polarised with its electric field in the horizontal plane. The light strikes two polarising filters, one behind the other. The first filter has its polaring direction at 25° to the horizontal and the second at 50° to the horizontal. What percentage of the intensity of the original light passes through the second filter?