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.

Explanation

`Pitch = ("distacne moved")/("number of complete rotations")`
`(4mm)/(4) = 1mm`
Least count = `("Pitch")/("no. fo divisions on circular scale")`
`=(1mm)/(200) = 0.005 mm = 0.0005 cm`