Two forces F1 and F2 applied on a crate/box lying on a frictionless ,horizontal surface as shown in the diagram The magnitude of force is greater than that of force F2. Describe the state of motion of the crate

Amichelson interferometer operating at a 600 nm wavelength has a 3.02-cm-long glass cell in one arm. to begin, the air is pumped out of the cell and mirror m2 is adjusted to produce a bright spot at the center of the interference pattern. then a valve is opened and air is slowly admitted into the cell. the index of refraction of air at 1.00 atm pressure is 1.00028.how many bright-dark-bright fringe shifts are observed as the cell fills with air?