JEE Main 2021PhysicsExperimental PhysicsEasyMCQ

JEE Main 2021 — Experimental Physics Question with Solution

JEE Main 2021 (26 Aug Shift 1)

Question

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 circular scale, and the main scale moves by 0.5 mm on a complete rotation. For a particular observation the reading on the main scale is 5 mm and the 20th  division of the circular scale coincides with reference line. Calculate the true reading.

Choose an option

Show full solutionCorrect option: C
Correct answer
C5.15 mm

Step-by-step explanation

L.C. of screw Gauge=0.550=0.01 mm
Zero error of screw Gauge =5×L.C.=5×0.01=0.05 mm
Reading of screw gauge = main scale reading + circular scale reading ×L.C.-Zero error =5+20×0.01-0.05=5.15 mm

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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.