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प्रश्न
You are given a thread and a metre scale. How will you estimate the diameter of the thread?
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उत्तर
The diametre of a thread is so small that it cannot be measured using a metre scale.Wrap the thread on a uniform smooth rod in such a way that the coils thus formed are very close to each other. Measure the length of the thread using a metre scale. The diameter of the thread is given by the relation,
Diameter = `"Length of thread"/"Number of turns"`
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