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An experiment is performed to find the refractive index of glass using a travelling microscope. In this experiment distances are measured by

1. a vernier scale provided on the microscope
2. a standard laboratory scale
3. a meter scale provided on the microscope
4. a screw gauge provided on the microscope

Correct answer: a vernier scale provided on the microscope

Solution

A travelling microscope measures small distances using the vernier scale fitted on it, allowing readings to about 0.01 mm.

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