According to the concept of length contraction, what happens to the length of an object as it approaches the speed of light and then slows down, eventually coming to a stop?

Length contraction means an object moving relative to an observer is measured as shorter along its direction of motion. As its speed increases toward the speed of light, the observed length contracts; as it slows down, the contraction decreases. When it comes to a stop relative to the observer, its measured length returns to its original rest length, so the correct choice is “It is observed as contracting and then expanding back to its original length.”

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