Question

what is the formula to find zero error correction in vernier calipers?

Answer 1

To find the zero error, close the jaws of Vernier Callipers. if zero line of vernier callipers coinsides with the zero of main scale then the zero error will be "zero".
Zero error will exist if zero line of vernier scale is not coinsiding with the zero of main scale.
-if zero line is on the right side, zero error will be positive.
-it will be negative if zero line is on the left side of the main scale..

Answer 2

Now, the formula

Zero Error= main scale reading + vernier scale reading


Suppose,
Main scale reading : 0.0cm
Vernier division coinsiding with main scale: 7 div
Vernier scale reading: 7 * 0.0
=0.07cm
Zero Error= 0.0cm + 0.07cm
= +0.07cm
Zero Correction= -0.07 cm
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