Y=StrainStress=AlFL=πR2lmgL
YΔY=mΔm+LΔL+2RΔR+lΔl
YΔY×100=100[10001+10001+2(0.20.001)+0.50.001]
=101+101+1+51=1014=1.4
JEE Main 2021 — Physics Mechanics
In order to determine the Young's Modulus of a wire of radius 0.2cm (measured using a scale of least count =0.001cm) and length 1m (measured using a scale of least count =1mm), a weight of mass 1kg (measured using a scale of least count =1g ) was hanged to get the elongation of 0.5cm (measured using a scale of least count 0.001cm). What will be the fractional error in the value of Young's Modulus determined by this experiment?
Held on 16 Mar 2021 · Verified 1 Jul 2026.
0.14
0.9
9
1.4
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