least count (vernier caliper)

Question

A vernier caliper has 10 vernier divisions coinciding with 9 main scale divisions (1 MSD = 1 mm). What is least count?

RankGuru · Accepted Answer

1. **Least Count (LC) Formula**: $LC = 1 	ext{ MSD} - 1 	ext{ VSD}$, where MSD is Main Scale Division and VSD is Vernier Scale Division.
2. **Information Given**: $1 	ext{ MSD} = 1$ mm. $10 	ext{ VSD} = 9 	ext{ MSD}$.
3. **Calculation of 1 VSD**:
   - $1 	ext{ VSD} = \frac{9}{10} 	ext{ MSD} = 0.9$ mm.
4. **Substitute into LC**:
   - $LC = 1 	ext{ mm} - 0.9 	ext{ mm} = 0.1$ mm.
5. **Result**: The instrument's least count is **$0.1$ mm**.

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least count (vernier caliper)

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