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AssertionA: If in five complete rotations of the circular scale, the distance travelled on the main scale of the screw gauge is 5 mm and there are 50…

JEE Main 2021 — Physics Mechanics

2021mcqmedium

AssertionA:\mathrm{Assertion}A:AssertionA: If in five complete rotations of the circular scale, the distance travelled on the main scale of the screw gauge is 5mm5\mathrm{mm}5mm and there are 505050 total divisions on a circular scale, then the least count is 0.001cm.0.001\mathrm{cm}.0.001cm.

ReasonR:\mathrm{Reason}R:ReasonR:

Least Count = Pitch  Total divisions on circular scale =\frac{\text{ Pitch }}{\text{ Total divisions on circular scale }}= Total divisions on circular scale  Pitch ​

In the light of the above statements, choose the most appropriate answer from the options given below.

Official previous-year question

Held on 27 Jul 2021 · Verified 6 Jul 2026.

Options

  1. A

    AAA is not correct but RRR is correct.

  2. B

    Both AAA and RRR are correct and RRR is the correct explanation of A.A.A.

  3. C

    AAA is correct but RRR is not correct.

  4. D

    Both AAA and RRR are correct and RRR is NOT the correct explanation of A.A.A.

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