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In order to determine the Young's Modulus of a wire of radius 0.2 cm (measured using a scale of least count =0.001 cm) and length 1m (measured using…

JEE Main 2021 — Physics Mechanics

2021mcqmedium

In order to determine the Young's Modulus of a wire of radius 0.2cm0.2\mathrm{cm}0.2cm (measured using a scale of least count =0.001cm=0.001\mathrm{cm}=0.001cm) and length 1m1m1m (measured using a scale of least count =1mm=1\mathrm{mm}=1mm), a weight of mass 1kg1\mathrm{kg}1kg (measured using a scale of least count =1g=1g=1g ) was hanged to get the elongation of 0.5cm0.5\mathrm{cm}0.5cm (measured using a scale of least count 0.001cm0.001\mathrm{cm}0.001cm). What will be the fractional error in the value of Young's Modulus determined by this experiment?

Official previous-year question

Held on 16 Mar 2021 · Verified 6 Jul 2026.

Options

  1. A

    0.140.14%0.14

  2. B

    0.90.9%0.9

  3. C

    99%9

  4. D

    1.41.4%1.4

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