JEE Main 2021PhysicsExperimental PhysicsMediumNumerical

JEE Main 2021 — Experimental Physics Question with Solution

JEE Main 2021 (25 Jul Shift 1)

Question

Student A and student B used two screw gauges of equal pitch and 100 equal circular divisions to measure the radius of a given wire. The actual value of the radius of the wire is 0.322 cm. The absolute value of the difference between the final circular scale readings observed by the students A and B is _______.

[Figure shows position of reference O when jaws of screw gauge are closed]

Given pitch =0.1 cm.

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Show full solutionCorrect answer: 13
Correct answer
13

Step-by-step explanation

For A,

Reading =MSR+CSR+Error

0.322=0.300+CSR+5×LC

0.322=0.300+CSR+0.005

CSR=0.017

For B, 

Reading =MSR+CSR+Error

0.322=0.200+CSR+0.092

CSR=0.030

Difference =0.030-0.017=0.013 cm

Division on circular scale =0.0130.001=13

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About this question

This is a previous-year question from JEE Main 2021, covering the Experimental Physics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.