In this worksheet, we will practice calculating the characteristics of an interference pattern produced by two beams of light traveling along different paths.
A 5.08-cm-long rectangular glass chamber is inserted into one arm of a Michelson interferometer using a 633-nm light source. This chamber is initially filled with air at standard atmospheric pressure but the air is gradually pumped out using a vacuum pump until a near perfect vacuum is achieved. How many fringes are observed moving by during the transition?
In a thermally stabilized lab, a Michelson interferometer is used to monitor the temperature to ensure it stays constant. The movable mirror is mounted on the end of a 1.00-m-long aluminum rod, held fixed at the other end. The light source is a He Ne laser, . The resolution of this apparatus corresponds to the temperature difference when a change of just one fringe is observed. Find the temperature difference. Use a value of for the thermal expansion coefficient of aluminum.
A microscope slide is 10.0 cm long. One end of the slide is separated from a glass plate by a sheet of paper, while the other end of the slide is in contact with the glass plate. The slide is illuminated from directly above by light from a sodium lamp that has a wavelength . A fringe pattern is seen along the slide, the pattern contains 14 fringes per centimeter. The slide is then immersed in an unknown liquid. When immersed in the liquid, 18 fringes per centimeter are observed. What is the liquid’s refractive index?
A chamber 6.3 cm long with flat parallel windows at its ends is placed in one arm of a Michelson interferometer. The light used has a wavelength of 500 nm in vacuum. While all the air is being pumped out of the chamber, 32 fringes pass by a point on the observation screen. What is the refractive index of air? Write the answer to six significant figures.