Question
A screw thread has 20 threads in 1 cm and its circular scale has 50 divisions. Calculate its pitch and least count.
✓
Answer
Number of threads $=20$
Distance covered in 20 threads $=10 mm$
Pitch of the screw gauge $=\frac{10}{20}=0.5 mm$
No of divisions on circular scale $=50$
Least count $=\frac{\text { pitch }}{\text { no. of divisions }}$
$=0.01 mm$
Distance covered in 20 threads $=10 mm$
Pitch of the screw gauge $=\frac{10}{20}=0.5 mm$
No of divisions on circular scale $=50$
Least count $=\frac{\text { pitch }}{\text { no. of divisions }}$
$=0.01 mm$
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