JEE Mains · Physics · STD 11 - Units,dimensions and measurement
- JEE Mains 2022
- Medium
- MCQ
A travelling microscope has \(20\) divisions per \(cm\) on the main scale while its Vernier scale has total \(50\) divisions and \(25\) Vernier scale divisions are equal to \(24\) main scale divisions, what is the least count of the travelling microscope \(..........\,cm\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(0.002\)
Step-by-step Solution
Detailed explanation
\(1\,MSD =\frac{1}{20}\,cm\)
\(1\,VSD =\frac{24}{25}\,MSD =\frac{24}{25} \times \frac{1}{20}\,cm\)
\(\therefore\) Least count \(=\frac{1}{20}\left(1-\frac{24}{25}\right)\,cm\)
\(=\frac{1}{20} \times \frac{1}{25}=\frac{1}{500}\,cm\)
\(=0.002\,cm\)
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