JEE Mains · Physics · STD 11 - 1. units,dimensions and measurement
The least count of the main scale of a screw gauge is \(1\, mm\). The minimum number of divisions on its circular scale required to measure \(5\,\mu m\) diameter of a wire is
- A \(50\)
- B \(200\)
- C \(100\)
- D \(500\)
Answer & Solution
Correct Answer
(B) \(200\)
Step-by-step Solution
Detailed explanation
\(\begin{array}{l} Least\,count = \frac{{Pitch}}{{No.of\,divisions\,on\,circular\,scale}}\\ 5 \times {10^{ - 6}} = \frac{{{{10}^{ - 3}}}}{N}\\ N = 200 \end{array}\)
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