A vernier scale has 10 divisions . It slides over a main scale whose pitch is 1.0 mm . If the number of division on the main scale , to the left- hand side of zero of the vernier scale is 4 and the 8th vernier scale division coincides with the main scale find the measurement.

Explanation

To solve the problem, we need to find the measurement using the given information about the Vernier scale and the main scale. Here are the steps to arrive at the solution:

### Step 1: Identify the Main Scale Reading (MSR)
The problem states that there are 4 divisions on the main scale to the left-hand side of the zero of the Vernier scale. Each division on the main scale is 1.0 mm.

**Calculation:**
- Main Scale Reading (MSR) = Number of divisions on the main scale × Pitch of the main scale
- MSR = 4 divisions × 1.0 mm/division = 4.0 mm
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