to measure the area of cross section by measuring diameter of a solid cylinder with vernier calliper

When the two jaws of the vernier are in contact,if the zero division of the main scale coincides with the zero of the vernier scale no ZERO error will be there.
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Formula :

1. Volume of the cylinder V = , ...
2. Least count of vernier calipers L.C = ...
3. Length (or) diameter of Cylinder = Main scale reading (a) cm + ( n*L.C ) cm.Part 2 Using the Caliper
   1. Slide one of the jaws against the object. The caliper has two types of jaws. ...
   2. Read the main scale where it lines up with the sliding scale's zero. The main scale on a Vernier caliper typically tells you the whole number plus the first decimal. ...
   3. Read the Vernier scale. ...
   4. Add the numbers together.