Answer:
Explanation:
a ) one vernier scale division = 19/20 mm.
Least count of vernier scale
= one main scale division - one vernier scale division
= ( 1 - 19 / 20) mm
= .05 mm
b ) uncertainty in the instrument = .05 mm / 1 mm
= 5 %
c ) When the zero mark of the vernier scale does not correspond to the zero Â
mark of the main scale then there is likelihood of error creeping in the reading by the scale. It is called zero error. Â