Relativity Question: Length Contraction of Moving Boxes

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This may seem like an odd question, but legnth contracts when something moves relative to an observer. Ok, what if I had two boxes both the same size. If one is moving in uniform motion with the observer & the other is moving at near the speed of light relative to the observer, would the box moving near the speed of light fight inside the other? To clarify, both boxes were originally measured when they were in uniform motion w/the observer. I also realize, length only contracts in the direction of motion... so perhaps we should say the first box is just a hair larger in the other two directions.

Hope that made sense, just trying to better understand the concept. Thanks much for your time.
 
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To simplify, assume the bigger box is stationary with respect to the observer and is open at both ends in the direction of motion of the other box. When the high speed box passes through the stationary box, it will look like both ends are inside as it passes through, even though intitally it was the same length.
 
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