The least count of a vernier calipers is 0.025 mm . If the 12th division of the vernier scale coinciles with a main scale division and the zero of the vernier scale is to the right of the zero of the main scale then the zero error is `"______"`

Options

A. `+0.3 cm`
B. `+0.03`
C. `+0.12 mm`
D. None of the above

Answer

To solve the problem, we need to determine the zero error of the Vernier calipers based on the information provided. Here’s a step-by-step solution:

### Step 1: Understand the Given Information
- The least count of the Vernier calipers is 0.025 mm.
- The 12th division of the Vernier scale coincides with a main scale division.
- The zero of the Vernier scale is to the right of the zero of the main scale.

### Step 2: Determine the Type of Zero Error
Since the zero of the Vernier scale is to the right of the zero of the main scale, this indicates a **positive zero error**. This means that the instrument reads a value greater than the actual measurement.

### Step 3: Calculate the Zero Error
The formula for calculating the zero error when the zero of the Vernier scale is to the right of the zero of the main scale is:
\[ \text{Zero Error} = \text{(Number of divisions of the Vernier scale that coincide)} \times \text{Least Count} \]

In this case, the 12th division of the Vernier scale coincides with the main scale division, so we can substitute the values:
- Number of coinciding divisions = 12
- Least Count = 0.025 mm

Now, we can calculate the zero error:
\[ \text{Zero Error} = 12 \times 0.025 \text{ mm} = 0.3 \text{ mm} \]

### Step 4: Conclusion
The zero error of the Vernier calipers is **0.3 mm**.

### Final Answer
The zero error is **0.3 mm**.

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