Question

How Vernier scale help in measurement of high

Answer 1

A vernier scale is a visual aid that allows the user to measure more precisely than could be done unaided when reading a uniformly divided straight or circular measurement scale. It is a subsidiary scale that indicates where the measurement lies in between two of the graduations on the main scale.
The main use of the vernier caliper is to measure the internal and the external diameters of an object. To measure using a vernier scale, the user first reads the finely marked "fixed" scale (i.e. the main scale; see the diagram). This measure is typically between two of the main scale's smallest graduations. The user then reads the vernier scale (see diagram), which measures between the smallest graduations on the fixed scale—providing much greater precision.