Respuesta :
According to you, the MP3 player that finishes the symphony first is;
A. Your player.
- We are told that they start playing same recorded version of same song on identical MP3 players.
- Now, due to the fact that you are standing stationary and your observer is in motion with the train, it means that there is a relative velocity between both of them.
- Now, because you are stationary and the observer is moving at a fast pace, following the time dilation principle it means you are the inertial observer without acceleration since you are standing and as such all clocks run slower with respect to your own clock.
- Since all clocks runs slower with respect to yours it means according to you, your MP3 player will finish the symphony first.
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