A rod has a length of 100 m in its own frame. What length is measured by an observer when it moves past at 0.60c along its length?
Answer and explanation
Correct answer: B. 80 m
- Step 1: .
- Step 2: m.
Answer
80 m.
Why not the others: 125 m: the contraction factor was applied the wrong way round. 60 m: the speed fraction was used directly. 100 m: length contraction was ignored.
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