Vernier constant is the

Options

A. value of one MSD divided by total number of divisions on the main scale
B. value of one VSD divided by total number of divisions on the vernier scale
C. total number of divisions on the main scale divided by total number of divisions on the vernier scale
D. difference between value of one main scale division and one vernier scale division

Answer

To find the Vernier constant, we follow these steps:

### Step-by-Step Solution:

1. **Understand the Definitions**:
- The Vernier constant (VC) is defined as the difference between the value of one main scale division (MSD) and one Vernier scale division (VSD).

2. **Identify the Values**:
- Let’s assume the value of one main scale division (MSD) is 1 mm.
- The value of one Vernier scale division (VSD) can be determined based on the number of divisions on the Vernier scale.

3. **Calculate the Value of One Vernier Scale Division**:
- If the Vernier scale has 10 divisions and the length of the Vernier scale is equal to the length of 9 main scale divisions, then:
\[ \text{Value of one Vernier scale division} = \frac{9 \text{ MSD}}{10} = \frac{9 \text{ mm}}{10} = 0.9 \text{ mm} \]

4. **Calculate the Vernier Constant**:
- Now, we can calculate the Vernier constant using the formula:
\[ \text{Vernier Constant} = \text{MSD} - \text{VSD} \]
- Substituting the values:
\[ \text{Vernier Constant} = 1 \text{ mm} - 0.9 \text{ mm} = 0.1 \text{ mm} \]

5. **Conclusion**:
- Therefore, the Vernier constant is 0.1 mm, which represents the least count of the Vernier caliper.

### Final Answer:
The Vernier constant is the difference between the value of one main scale division and one Vernier scale division, which in this case is 0.1 mm.

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