question_answer

The screw of a spherometer moves by 4 mm. when its circular scale is given four complete rotations. If circular scale has 200 divisions, calculate pitch and least count of the spherometer.

Answer:

                \[Pitch=\frac{dis\tan ce\,moved}{number\,\,of\,complete\,rotations}=\frac{4mm}{4}=1mm\]                 \[Least\,count=\frac{Pitch}{no.\,of\,divisions\,on\,circular\,scale}=\frac{1mm}{200}=0.005mm=0.0005\,cm\]