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Experimental Physics

JEE Main level, single correct, medium

41 of 70

Question 41 of 70

One main scale division of a vernier callipers is $a$ $cm$ and ${n}^{th}$ division of the vernier scale coincide with ${\left(n-1\right)}^{th}$ division of the main scale. The least count of the callipers in $mm$ is :

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Answer: (D) $\dfrac{10a}{n}$

\left(n-1\right)a=n\left({a}^{'}\right)

{a}^{'}=\dfrac{\left(n-1\right)a}{n}

∴L.C.=1MSD-1VSD

=\left(a-{a}^{'}\right)cm

=a-\dfrac{\left(n-1\right)a}{n}

=\dfrac{na-na+a}{n}=\dfrac{a}{n}cm

=\left(\dfrac{10a}{n}\right)mm

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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JEE Main Physics practice question on Experimental Physics (Experimental Physics), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

One main scale division of a vernier callipers is aaa cmcmcm and nth{n}^{th}nth division of the vernier scale coincide with (n−1)th{\left(n-1\right)}^{th}(n−1)th division of the main scale. The least count of the callipers in mmmmmm is :

JEE Main question paper PDF

More Physics practice

One main scale division of a vernier callipers is $a$ $cm$ and ${n}^{th}$ division of the vernier scale coincide with ${\left(n-1\right)}^{th}$ division of the main scale. The least count of the callipers in $mm$ is :