JEE Main 2021PhysicsCurrent ElectricityMediumMCQ

JEE Main 2021 — Current Electricity Question with Solution

JEE Main 2021 (01 Sep Shift 2)

Question

Two resistors R1=(4±0.8) Ω and R2=(4±0.4) Ω are connected in parallel. The equivalent resistance of their parallel combination will be :

Choose an option

Show full solutionCorrect option: D
Correct answer
D(2±0.3) Ω

Step-by-step explanation

ΔRR2=ΔR1R12+ΔR2R22
ΔR=R2ΔR1R12+ΔR2R22
=220.842+0.442
=[0.2+0.1]=0.3
Rnet =R+ΔR=2±0.3

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About this question

This is a previous-year question from JEE Main 2021, covering the Current Electricity 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.