6. This micrometer has zero error.
The zero marking on the thimble is below the datum line. So this micrometer
has a positive zero error.
How do we count the zero error?
In this case we will take the reading on the thimble.
Thimble reading = 0.03 mm
So the micrometer has a zero error of +0.03 mm.
Whatever reading we take on this micrometer we would have to
subtract +0.03 mm
7. The zero marking on the thimble is above the datum line. So this micrometer
has a negative zero error.
In this case we will have to count the number of divisions on the thimble
between the zero marking and the datum line.
No. of divisions = 3
Measurement of each division = 0.01mm
So the micrometer has a zero error of -0.03 mm.
Whatever reading we take on this micrometer we would have to
subtract -0.03 mm
