In part (a), candidates could not give and acceptable difference between plane polarized light and
ordinary light. Majority of the candidates failed add “perpendicular” to their  explanation.
In part (b) performance was fair as most responding candidates were able to give two uses of  polaroids.
The expected answers are:
 In plane polarized light, the vibrations of the particles are confined to a single plane perpendicular to the direction of propagation of light while in ordinary light, the vibrations of the particles is in all planes.
Uses of Polaroid
-    sunglasses (to reduce the intensity of sunlight)
-    to eliminate reflected light/glare
-    sacharimetry/measurement of concentration of sugar solution.
-     stress analysis/photo elasticity.