Special Relativity and length contraction

AI Thread Summary
In the discussion on special relativity and length contraction, the focus is on measuring the length of a moving meter stick, which appears shorter to an observer due to its high speed. The proper length of the meter stick is one meter, as measured by someone moving with it. When the stick moves past an observer and is measured at 1.00 ft, this indicates length contraction has occurred. The confusion arises from understanding that the length observed is not the proper length but rather a contracted length due to relative motion. The discussion emphasizes the importance of distinguishing between proper length and contracted length in the context of special relativity.
ledhead86
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A meter stick moves past you at great speed. Its motion relative to you is parallel to its long axis.

If you measure the length of the moving meter stick to be 1.00 ft (1ft=.3048 m), for example by comparing it to a one-foot ruler that is at rest relative to you, at what speed is the meter stick moving relative to you?


The only thing I can figure out is that one foot is the proper length. I'm completely confused about the rest.
 
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OK, here's a hint: This is a problem in length contraction.

What do you know about length contraction?
 
ledhead86 said:
The only thing I can figure out is that one foot is the proper length.


No, the proper length is the length that would be measured by someone who is moving along with the meter stick (like a witch riding a broomstick :devil: ). So the proper length of a meter stick is one meter.
 
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