Question

what is the formula if the reading of main scale is known and number of vernier scale divisions coonciding with main scals are known ​

Answer 1

The Vernier caliper is an extremely precise measuring instrument; it is used to measure internal and external distances extremely accurately – the error may be as little as 0.05 mm – depending on the make.The VERNIER is a small movable graduated scale for obtaining fractional parts of subdivisions on a fixed main scale of any measuring instrument. With a normal scale we may be able to measure down to 0.50 mm or so, while with a vernier scale the least count may be 0.10 mm. Usually vernier calipers have both imperial (inches) and metric (mm) scales