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rede96
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I was trying to understand a few of the relativity basics that seem to have me confused. Below is a thought experiment and some questions, I would really appreciate any help to improve my understanding. Thanks
Imagine a large, circular, tube like space station. Free to spin around the inside diameter of the space station is a large rigid ‘pointer’ (As in diagram below) So the set up is a bit like a compass.
There are two clocks at points A and points B, which are exactly 180 degrees apart. When the ends of the pointer line up exactly with points A and B, they do so simultaneously (as seen from the centre of the space station) and both clocks synchronise.
Say the distance between points A and B is 360,000 km and assume 300,000 km per sec as the speed of light.
Scenario 1
The space station turns the pointer until the points align and clocks synchronise. A rocket ship traveling at 0.6c passes over points A and B in a straight line. As it passes over point A, (event 1) it starts a clock on the rocket ship and the time of the clock at Point A is taken by the space station.
When the rocket ship passes over point B, (event 2) the clock on the rocket ship stops and the space station makes a note of the time on the clock at point B
The rocket ships signals the elapsed time on its clock to the space station, which was 1.6 seconds. The space station then compares this with the time difference between the two clocks A and B, which was 2 seconds.
So both the space station and the rocket ship agree that time on the rocket ship ran slower between the two events, as it was moving relative to the space station.
However as there are no special frames of reference, then it is equally valid for the rocket ship to say it was at rest and the space station was moving. However even if this was the case, the clock on the rocket ship would still have shown less time pass between the two events then the two clocks on the space station. (Due to length contraction I am assuming?)
Is this correct? If so I am confused as to how the rocket ship’s clock will always show less time between the two events than the space station.
Scenario 2
Remove the clocks, but this time when the pointer aligns at points A and B, A and B send light signals to each other, which are reflected back to a receiver at the centre point of the pointer. So each light source travels 360,000 km from its origin in one direction and 180,000 km back to the centre point.
If the receiver at the centre point receives both light signals at the same time, (same time wrt to the centre point) then doesn’t this suggest that the one way speed of light is the same in both directions?
Thanks.
Imagine a large, circular, tube like space station. Free to spin around the inside diameter of the space station is a large rigid ‘pointer’ (As in diagram below) So the set up is a bit like a compass.
There are two clocks at points A and points B, which are exactly 180 degrees apart. When the ends of the pointer line up exactly with points A and B, they do so simultaneously (as seen from the centre of the space station) and both clocks synchronise.
Say the distance between points A and B is 360,000 km and assume 300,000 km per sec as the speed of light.
Scenario 1
The space station turns the pointer until the points align and clocks synchronise. A rocket ship traveling at 0.6c passes over points A and B in a straight line. As it passes over point A, (event 1) it starts a clock on the rocket ship and the time of the clock at Point A is taken by the space station.
When the rocket ship passes over point B, (event 2) the clock on the rocket ship stops and the space station makes a note of the time on the clock at point B
The rocket ships signals the elapsed time on its clock to the space station, which was 1.6 seconds. The space station then compares this with the time difference between the two clocks A and B, which was 2 seconds.
So both the space station and the rocket ship agree that time on the rocket ship ran slower between the two events, as it was moving relative to the space station.
However as there are no special frames of reference, then it is equally valid for the rocket ship to say it was at rest and the space station was moving. However even if this was the case, the clock on the rocket ship would still have shown less time pass between the two events then the two clocks on the space station. (Due to length contraction I am assuming?)
Is this correct? If so I am confused as to how the rocket ship’s clock will always show less time between the two events than the space station.
Scenario 2
Remove the clocks, but this time when the pointer aligns at points A and B, A and B send light signals to each other, which are reflected back to a receiver at the centre point of the pointer. So each light source travels 360,000 km from its origin in one direction and 180,000 km back to the centre point.
If the receiver at the centre point receives both light signals at the same time, (same time wrt to the centre point) then doesn’t this suggest that the one way speed of light is the same in both directions?
Thanks.