Light waves were once thought by physicists to require a medium called ether to propagate through. In the year 1887, an experiment was carried out to try and measure the speed of light waves relative to the ether. An interferometer was used. The interferometer had a velocity relative to the ether due to the motion of Earth through the ether. The diagram shows an interferometer where the direction of is perpendicular to the arm AB and parallel to the arm CD of the interferometer. The length of the arms of the interferometer was the same. Which of the following would contribute to the net velocities of light waves relative to the interferometer’s beam splitter if it was assumed that the light waves and the interferometer move relative to a stationary ether?
The diagram shows an interferometer. The mirror in one of the interferometer’s arms moves a distance . Which color line on the graph of intensity measured at the detector against correctly represents the change of intensity as the mirror moves?
The diagram shows an interferometer. The mirror in one of the interferometer’s arms is rotated through a small angle. Which of the following statements about the intensity of the light measured by the detector after the mirror rotates must be true?