Einstein's train (simultaneity)

AI Thread Summary
In the discussion about Einstein's train scenario, an observer moving along a train sees two light signals emitted from either end of the car. The observer concludes that he must be at the midpoint of the train when he perceives the signals simultaneously. However, confusion arises regarding which signal was sent first from his perspective. A suggestion is made to consider that both signals could have been sent at the same time, challenging the observer's initial assumptions. This highlights the complexities of simultaneity in different reference frames.
sunrah
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Homework Statement



We have an observer moving along a moving train car with speed v (assumed to be relative velocity between observer and car). Two light signals are emitted from each end of the car.

a)Where is the observer if he sees both signals simultaneously?
b)From his point of view, which signal was sent first?

Homework Equations


None

The Attempt at a Solution



I simply took the frame in which the observer is at rest and said the train is moving past with speed v. This is the typical Einstein's train scenario with the observer on the platform (except the train is pretty slow). So our observer must be passing the middle of the train when he sees the lights.

But why the second part of the question? So I must be wrong.
 
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sunrah said:

Homework Statement



We have an observer moving along a moving train car with speed v (assumed to be relative velocity between observer and car). Two light signals are emitted from each end of the car.

a)Where is the observer if he sees both signals simultaneously?
b)From his point of view, which signal was sent first?


Homework Equations


None


The Attempt at a Solution



I simply took the frame in which the observer is at rest and said the train is moving past with speed v. This is the typical Einstein's train scenario with the observer on the platform (except the train is pretty slow). So our observer must be passing the middle of the train when he sees the lights.

But why the second part of the question? So I must be wrong.

Have you considered the possibility "neither, they were sent at the same time"
 
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