Physics · Units, Dimensions & Error Analysis

JEE Main 2024 — 8 April, Shift 1 — Question 48

The diameter of a sphere is measured using a vernier caliper whose 9 divisions of main scale are equal to 10 divisions of vernier scale. The shortest division on the main scale is equal to 1 mm . The main scale reading is 2 cm and second division of vernier scale coincides with a division on main scale. If mass of the sphere is 8.635 g , the density of the sphere is:

  1. Option A:

    2.5 g/cm32.5 \mathrm{~g} / \mathrm{cm}^{3}

  2. Option B:

    1.7 g/cm31.7 \mathrm{~g} / \mathrm{cm}^{3}

  3. Option C:

    2.2 g/cm32.2 \mathrm{~g} / \mathrm{cm}^{3}

  4. Option D:

    2.0 g/cm32.0 \mathrm{~g} / \mathrm{cm}^{3}

    Correct

Answer: D

Step-by-step solution

Given 9MSD=10VSD9 \mathrm{MSD}=10 \mathrm{VSD}

mass =8.635 g=8.635 \mathrm{~g}

LC=1MSD−1VSD\mathrm{LC}=1 \mathrm{MSD}-1 \mathrm{VSD}

LC=1MSD−910MSD\mathrm{LC}=1 \mathrm{MSD}-\frac{9}{10} \mathrm{MSD}

LC=110MSD\mathrm{LC}=\frac{1}{10} \mathrm{MSD}

LC=0.01 cm\mathrm{LC}=0.01 \mathrm{~cm}

Reading of diameter =MSR+LC×VSR=\mathrm{MSR}+\mathrm{LC} \times \mathrm{VSR}

=2 cm+(0.01)×(2)=2.02 cm\begin{aligned} & =2 \mathrm{~cm}+(0.01) \times(2) & =2.02 \mathrm{~cm} \end{aligned}

Volume of sphere =43π(d2)3=43π(2.022)3=\frac{4}{3} \pi\left(\frac{d}{2}\right)^{3}=\frac{4}{3} \pi\left(\frac{2.02}{2}\right)^{3}

=4.32 cm3=4.32 \mathrm{~cm}^{3}

Density = mass  volume =8.6354.32=1.998∼2.00 g=\frac{\text { mass }}{\text { volume }}=\frac{8.635}{4.32}=1.998 \sim 2.00 \mathrm{~g}

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Physics
Chapter
Units, Dimensions & Error Analysis
Topic
Vernier Calipers and Screw Gauge
The diameter of a sphere is measured using a vernier caliper whose 9… | JEE Main 2024 PYQ with Solution · DhiX AI