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In a Screw Gauge, fifth division of the circular scale coincides with the reference line when the ratchet is closed. There are 50 divisions on the…

JEE Main 2021 — Physics Mechanics

2021mcqeasy

In a Screw Gauge, fifth division of the circular scale coincides with the reference line when the ratchet is closed. There are 505050 divisions on the circular scale, and the main scale moves by 0.5mm0.5\mathrm{mm}0.5mm on a complete rotation. For a particular observation the reading on the main scale is 5mm5\mathrm{mm}5mm and the 20th {20}^{\text{th }}20th  division of the circular scale coincides with reference line. Calculate the true reading.

Official previous-year question

Held on 26 Aug 2021 · Verified 6 Jul 2026.

Options

  1. A

    5.20mm5.20\mathrm{mm}5.20mm

  2. B

    5.00mm5.00\mathrm{mm}5.00mm

  3. C

    5.15mm5.15\mathrm{mm}5.15mm

  4. D

    5.25mm5.25\mathrm{mm}5.25mm

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