Given here, main scale reading, MS=401cm
And, 50×VS=49×MS
Least count of travelling microscope is LC=MS−VS
=MS−5049MS
=501×MS
=501×401cm=20001×10−2m
=5×10−6m
A travelling microscope is used to determine the refractive index of a glass slab. If 40 divisions are there in 1cm on main scale and 50 Vernier scale divisions are equal to 49 main scale divisions, then least count of the travelling microscope is _____ ×10−6m.
Held on 26 Jun 2022 · Verified 6 Jul 2026.
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