Polaroid only transfers light parallel through it, but when unpolarized light strikes on it, where the unpolarized light goes, how does it absorbs unpolarized light?, or it relfects it?
The microscopic crystals in the polaroid are aligned in the same direction. And the molecules in the crystal are alinged in this direction. Electrons in the molecules of these crystals are relatively free to move along one axis of the crystal but not others, because of the arrangement of the atoms in the molecules. If the electric field of incident light is polarised parallel to this axis, it causes a lot of electron movement. The energy given to electrons is then dissipated by being transferred to the surrounding atoms producing a tiny amount of heat For other directions of the electric field of incident light, this energy dissipation is much less - so this light passes through without significant loss of energy.
