Why Is a Moving Meter Stick Measured at 80 cm Assumed to Be 100 cm at Rest?

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The discussion centers on the relativistic measurement of a moving meter stick, specifically why a meter stick measured at 80 cm is assumed to have a proper length of 100 cm when at rest. The formula L = Lo/gamma is utilized, where gamma represents the Lorentz factor, defined as gamma = 1 / (1 - (v/c)^2)^(1/2). The proper length, Lo, is established as 100 cm, which is the standard length of a meter stick in its rest frame, equating to 1 meter.

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cmantzioros
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I'm attempting a question that reads: A moving meter stick is measured to be 80 cm. What is its speed?

The related formula is L = Lo/gamma where gamma = 1 / (1 - (v/c)^2)^(1/2)

I looked at the solution provided and the first statement is: Lo = 100cm. I understand the rest from there but I have no idea where this 100cm comes from. Can anyone explain?
 
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cmantzioros said:
I looked at the solution provided and the first statement is: Lo = 100cm. I understand the rest from there but I have no idea where this 100cm comes from. Can anyone explain?
They said it was a "meter stick", and 1 meter = 100 cm. This must be its length in its own rest frame.
 

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