Q. Two friends, Al and Jo, have a combined mass of 164kg. At the ice skating rink, they stand close together on skates, at rest and facing each other. By their arms, they push on each other for 1 second and move off in opposite directions. Al moves off with a speed of 7.8 m/sec in one direction and Jo moves off with the speed of 8.60 m/sec in the other. You can assume friction is negligible.
Q. A Michelson interferometer is used to measure the wavelength of light emitted from a monochromatic source. As the adjustable mirror is gradually moved through a distance DA = 0.0265 mm, an observer counts 411 alternations between bright and dark fields. What is the wavelength of the monochromatic light used in this experiment?