Question

How will you measure the diameter of a wire using a screw gauge?

Answer 1

The following procedure is used to measure the diameter of a wire
(a). Calculate the least count and zero error of the screw gauge.
(b). Place the wire in between the studs. Turn the ratchet clockwise so as to hold the wire gently in between the studs. Record the main scale reading.
(c). Now record the division of circular scale that coincides with the base line of the main scale. This circular scale division multiplied by the least count will give circular scale reading.
(d). The observed diameter is obtained by adding the circular scale reading to the main scale reading. Subtract the zero error if any, with its proper sign, from the observed diameter to get the true diameter.