Here is a question one of my physics teachers mentiones a long time ago.(adsbygoogle = window.adsbygoogle || []).push({});

Say you have a 10 ft. car and a 10 ft. barn, so the car will just barely fit. Now say the car saw traveling at an appreciable fraction of the speed of light, and you are traveling next to the car, on the line perendicular between the car and the barn. It appears to you that the barn is smaller than 10 ft., and the car won't fit in the barn. Now imagine the same situation, but you are standing next to the barn. The car now looks less than 10ft. long, so it should fit in the barn with room to spare.

I can understand things like simultaniety being an illusion. But how can the car both fit and not fit in the barn? Thanks ahead of time, and I hope this isn't to stupid of a question.

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# Frame of reference

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