An astronaut is traveling in a space vehicle that has a speed of 0.500c relative to Earth. The astronaut measures his pulse rate at 74.0 per minute. Signals generated by the astronaut's pulse are radioed to Earth when the vehicle is moving perpendicularly to a line that connects the vehicle with an Earth observer.
What pulse rate does the Earth observer measure?
What would be the pulse rate if the speed of the space vehicle were increased to 0.940c?