Question

when is a vernier callipers said to be from zero error?​

Answer 1

Answer:

In case of vernier calipers it occurs when a zero on main scale does not coincide with a zero on vernier scale. The zero error may be of two types i.e. when the scale is towards numbers greater than zero it is positive else negative.

Explanation:

Answer 2

Answer:

unscrew the slider and move it to the left such that the both jaw touch each other,now check themain scale reading and the vernier scale reading are equal if not its called as zero error

Explanation: