JEE Mains · Physics · STD 11 - 1. units,dimensions and measurement
A travelling microscope is used to determine the refractive index of a glass slab. If \(40\) divisions are there in \(1 \; cm\) on main scale and \(50\) Vernier scale divisions are equal to \(49\) main scale divisions, then least count of the travelling microscope is \(\dots \; \times 10^{-6} \; m\)
- A \(2\)
- B \(3\)
- C \(4\)
- D \(5\)
Answer & Solution
Correct Answer
(D) \(5\)
Step-by-step Solution
Detailed explanation
\(50 \; VSD =49 \; MSD\) \(1 \; VSD =\frac{49}{50} \; MSD\) Least count \(=1 MSD -1 VSD\) \(=\left(1-\frac{49}{50}\right) MSD =\frac{1}{50} \; MSD\) \(1 \; MSD =\frac{1}{40} \; cm\) Least count \(=\frac{1}{50 \times 40} \; cm\)…
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