Column - I gives certain physical terms associated with flow of current through a metallic conductor. Column - II gives some mathematical relations involving electrical quantities. Match Column - I and Column - II with appropriate relations. Column - I; Column - II (A) Drift Velocity; (P) mne^2ρ (B) Electrical Resistivity; (Q) nevd (C) Relaxation Period; (R) eE/mτ (D) Current Density; (S) E/J

NEET UG 2021 · Physics · Question 4

NEET 2021 Physics, question 4

Question 4 of the NEET 2021 paper (code O1) is a Physics question from Current Electricity. Its idea, Microscopic Model of Resistivity, was asked only this once in NEET 2017–2026. The NTA final answer key gives option 3.

Updated 2026-10-08

Q4 · Physics

\frac{m}{ne^{2}\rho}

Column - I	Column - II
(A) Drift Velocity	(P) $\frac{m}{ne^{2}\rho}$
(B) Electrical Resistivity	(Q) $nev_d$
(C) Relaxation Period	(R) $\frac{eE}{m}\tau$
(D) Current Density	(S) $\frac{E}{J}$

1 (A)-(R), (B)-(P), (C)-(S), (D)-(Q) 2 (A)-(R), (B)-(Q), (C)-(S), (D)-(P) 3 (A)-(R), (B)-(S), (C)-(P), (D)-(Q) Official answer 4 (A)-(R), (B)-(S), (C)-(Q), (D)-(P)

Official answer: option 3 · NTA final answer key

Same idea

The only question on Microscopic Model of Resistivity

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The chapter

Current Electricity in ten years of NEET

34 questions from 2017–2026, asked in 10 of 10 papers, about 3.2 a paper. Ohm's Law and Resistance alone had 28.

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The only question on Microscopic Model of Resistivity

Current Electricity in ten years of NEET

Current Electricity: questions per paper