Question

How will you find the thickness of a one rupee coin?

Answer 1

1. Determine the pitch, the least count and the zero error of the screw gauge
2.  Place the coin between the two studs
3.  Rotate the head until the coin is held firmly but not tightly, with the help of the ratchat
4.  Note the reading of the pitch scale crossed by the head scale (PSR) and the head scale division that coincides with the pitch scale axis (HSC)
5.  The width of the coin is given by PSR + CHSR (Corrected HSR). Repeat the experiment for different positions of the coin
6.  Tabulate the readings
7.  The average of the last column readings gives the width of the coin

S.No.	P.S.R (mm)	H.S.C (division)	CHSC = HSC ± ZC (Division)	CHSR = CHSC x LC (mm)	Total reading = PSR + CHSR (mm)
1.					mean = mm
2.

Thickness of the coin = …….. mm