If a star 100 light-years away explodes, the time for the gravitational waves to reach Earth is 100 years as measured from
A)any uniformly moving reference frame.
B)any accelerating reference frame.
C)any reference frame, accelerated or not.
D)the reference frame of the waves.
E)Earth.

Question

Quizplus · Accepted Answer

Gravitational waves travel at the speed of light, which is a constant from any reference frame. Therefore, the time for the waves to reach Earth is simply the distance to the star divided by the speed of light, which is 100 years. This is as measured from Earth, which is at rest in its own reference frame. From any other reference frame, the distance and time may appear different due to relativistic effects, but the overall time for the waves to reach Earth will still be 100 years when measured by any observer.

If a Star 100 Light-Years Away Explodes, the Time for the Gravitational