Q. In a screw gauge, $5$ complete rotations of the screw cause it to move a linear distance of $0.25 \, cm$ . There are $100$ circular scale divisions. The thickness of a wire measured by this screw gauge gives a reading of $4$ main scale divisions and $30$ circular scale divisions. Assuming negligible zero error, what is the thickness (in mm) of the wire?
NTA AbhyasNTA Abhyas 2020Physical World, Units and Measurements
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