Cinema 3D glasses have polarising lenses aligned 90o from each other. The left eye contains a horizontal polariser and the right lens contains a vertical polariser.
A person stands in front of a mirror and closes their left eye.
Plane-polarised electromagnetic waves of radio frequency are transmitted by a vertical aerial and have an amplitude A. They are received by a second aerial rotated at angle compared to the transmitting aerial.
Which of the following expressions is proportional to the power received by the second aerial?
Light from a lamp is incident on a polarising filter that has a horizontal transmission axis. The incident light has intensity and the transmitted light has intensity . The filter is rotated by 2π.
Which graph correctly shows the variation of the ratio with angle ?
The intensity of radiation from a star is given by . The intensity of light at the surface of one of its planets, a distance r from the star is . The distance between the star and a second planet is 3r.
What is the intensity of light from the star on this second planet?