JEE Main · 2022 · 26 Jun 2022 · Shift 2 · Units & Measurement

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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 ______ m.

Answer: 5

Solution

Given: 50 VSD = 49 MSD, so 1 VSD = MSD

Least count = 1 MSD - 1 VSD = MSD = MSD

Since 40 divisions = 1 cm:


Therefore:


The answer is 5.

JEE Main · 2022 · 26 Jun 2022 · Shift 2 · Integer answer

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