Two starships, the Enterprise and the Constitution, are approaching each other head-on from a great distance. The separation between them is decreasing at a rate of 772.5 km/s. The Enterprise sends a laser signal toward the Constitution. a. If the Constitution observes a wavelength λ=675.3nm, what wavelength was emitted by the Enterprise?
b. If a microwave oven produces electromagnetic waves with a frequency of 2.75 GHz, what is their wavelength?