1) An astronaut is traveling in a space vehicle that has a speed of0.450crelative to Earth. The astronaut measures his pulse rate at82.0per 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.

(a) What pulse rate does the Earth observer measure? min¹ (b) What would be the pulse rate if the speed of the space vehicle were increased to 0.990c? min¹

2)A star is 18.2 ly (light-years) from Earth.

(a)At what constant speed (in m/s) must a spacecraft travel on its journey to the star so that the Earth-star distance measured by an astronaut onboard the spacecraft is 4.76 ly? m/s?

(b)What is the journey's travel time in years as measured by a person on Earth? yr?

(c)What is the journey's travel time in years as measured by the astronaut? Yr?