describe stepwise the producer to measure diameter of a wire using screw gauge
Answers
Lab Procedure
1 Determine the pitch and least count of the screw gauge using the equations (1) and (2) respectively..
2 Bring the anvil and screw in contact with each other and find the zero error. Do it three times and record them. If there is no zero error, then record ‘zero error nil’.
3 Move the screw away from the anvil and place the lead shot and move the screw towards the anvil using the ratchet head. Stop when the ratchet slips without moving the screw.
4 Note the number of divisions on the pitch scale that is visible and uncovered by the edge of the cap. The reading N is called the pitch scale reading(PSR)
5 Note the number (n) of the division of the circular scale lying over the reference line.
6 Repeat steps 4 and 5 after rotating the lead shot by 900 for measuring the diameter in a perpendicular direction. Record the observations in the tabular column.
7 Find total reading using the equation 3 and apply zero correction in each case.
8 Take the mean of different values.
Note: Place the other objects like, wire, glass plate etc between the screw and the anvil and follow the above procedure to find the measurement.