- #1
Al68
Let's say we have a ship following a buoy toward earth. The ship and buoy are at rest relative to each other, a distance of 10 light years apart, in the ship's frame. The distance between the ship and buoy is 5 light years in Earth's frame. They are approaching Earth at a relative velocity of 0.866c. When the buoy passes earth, an observer on Earth starts his clock at t = 0, and an observer on the buoy starts his clock at t' = 0. An observer on the ship also starts his clock at t' = 0, since he is at rest with the buoy, and they planned this ahead of time. At t = 5.77 years in Earth's frame, the ship reaches Earth and turns around. At t' = 11.55 years in the frame of the ship and buoy, the ship reaches Earth and turns around and leaves Earth at 0.866c. There is a second buoy approaching Earth from the opposite direction of the ship, now at rest with the ship, at 0.866c relative to earth. This second buoy is now 10 light years behind the ship, in the ship's and the second buoy's frame. This distance between the ship and the second buoy is now 5 light years in Earth's frame. At t = 11.55 years in Earth's frame, the second buoy passes earth. At t' = 23.1 years, the second buoy passes Earth in the ship's frame.
The total time between the event of the first buoy passing Earth and the second buoy passing Earth (in the opposite direction) is 11.55 years in Earth's frame, and 23.1 years in the ship's frame. At t = t' = 0, the ship was 10 light years from Earth in the ship's frame and the ship was 5 light years from Earth in Earth's frame. At t = 11.55 years, the ship was 5 light years from Earth again in Earth's frame. At t' = 23.1 years, the ship was again 10 light years from Earth in the ship's frame.
Would these results be correct?
Thanks,
Alan
The total time between the event of the first buoy passing Earth and the second buoy passing Earth (in the opposite direction) is 11.55 years in Earth's frame, and 23.1 years in the ship's frame. At t = t' = 0, the ship was 10 light years from Earth in the ship's frame and the ship was 5 light years from Earth in Earth's frame. At t = 11.55 years, the ship was 5 light years from Earth again in Earth's frame. At t' = 23.1 years, the ship was again 10 light years from Earth in the ship's frame.
Would these results be correct?
Thanks,
Alan
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