Understanding Relativity: Deciphering Time and Space Graphs

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http://i37.tinypic.com/avpjsh.jpg

i can't understand the graph.

i know that its time and x axes graph

but i can imagine the pole moving
or the barn moving to the runner

all i see is some lines

the part when the barn moving to the runner is the hardest graph

i don't know what happening there
 
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lom said:
… the part when the barn moving to the runner is the hardest graph

i don't know what happening there

Hi lom! :smile:

it's like two trains on adjacent track …

you're on one train, looking at the other, and you can't tell which train is moving.

Here, the barn is one train, and the runner is the other train.

You can regard the runner as stationary, and in that case the barn must be moving.

Since they're getting closer (well, until he gets inside! :rolleyes:), that means the barn must be moving backwards. :smile:

(and world-lines always slope towards the direction of motion)
 
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