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:
(A) Drift Velocity
(B) Electrical Resistivity
(C) Relaxation Period
(D) Current Density
Column - II:
(P) $\dfrac{m}{ne^2\rho}$
(Q) $nev_d$
(R) $\dfrac{eE}{m}\tau$
(S) $\dfrac{E}{J}$
Answer: (B) (A)-(R), (B)-(S), (C)-(P), (D)-(Q)
(A) Drift velocity: $v_d = \dfrac{eE}{m}\tau$ (R).
(B) Resistivity: $\rho = \dfrac{E}{J}$ (from $J = \sigma E$) (S).
(C) Relaxation time: from $\rho = \dfrac{m}{ne^2\tau}$, $\tau = \dfrac{m}{ne^2\rho}$ (P).
(D) Current density: $J = nev_d$ (Q).
(A)-(R), (B)-(S), (C)-(P), (D)-(Q).
Solution by Sreeraj P, M.Sc Physics