NEET 2020 Physics Question 146 Solution

The pitch of a screw gauge is the linear distance advanced by the screw on the main scale when the circular cap/thimble is rotated through one complete revolution ($$360^\circ$$). The least count ($$\text{LC}$$) is the smallest distance that can be measured using the instrument, given by: $$\text{LC} = \frac{\text{Pitch}}{\text{Total number of divisions on circular scale } (N)}$$

$$\text{Pitch} = \text{LC} \times N$$

Given: - Least count = $$0.01\text{ mm}$$ - Total circular scale divisions $$N = 50$$ $$\text{Pitch} = 0.01\text{ mm} \times 50 = 0.50\text{ mm} = 0.5\text{ mm}$$

The pitch is precisely $$0.5\text{ mm}$$, which corresponds directly to Option (3).