In a screw gauge, the reference line of the main scale coincides with the fifth division of the circular scale when the two studs are in contact. There are 100 divisions on the circular scale and the pitch is 0.1 mm. Measuring a sphere, the main scale reads 5 mm and the 50th circular division coinc…

Question

In a screw gauge, the reference line of the main scale coincides with the fifth division of the circular scale when the two studs are in contact. There are 100 divisions on the circular scale and the pitch is 0.1 mm. Measuring a sphere, the main scale reads 5 mm and the 50th circular division coincides with the reference line. The diameter of the sphere is mm.

Accepted Answer

(1) 5.045. L.C. =(0.1)/(100)=0.001 mm. Positive zero error =5×0.001=0.005 mm (reference at the 5th division when closed). Observed =5+50×0.001=5.05 mm. Corrected =5.05-0.005=5.045 mm.

Step-by-step solution

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