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A straight metallic wire of resistance R is used in the situations of Column-I. Match each with the resulting effect in Column-II. Column-I: (A) A charged capacitor is connected across the ends of the wire (B) The wire is moved at constant velocity perpendicular to its length in a uniform magnetic field perpendicular to the plane of motion (C) The wire is placed in a constant electric field directed along its length (D) A battery of constant emf is connected across the ends of the wire Column-II: (P) A constant current flows through the wire (Q) Thermal energy is generated in the wire (R) A constant potential difference develops between the ends of the wire (S) Charges of constant magnitude appear at the ends of the wire

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

Correct answer: (A)-(Q), (B)-(S), (C)-(R), (D)-(P)

Solution

(A) The capacitor discharges through R, dissipating heat (Q). (B) Motional emf separates charge giving fixed charges at the ends (S), with no steady current in an open wire. (C) An external E along the wire maintains a constant PD across its ends (R). (D) A constant emf source drives a constant current (P).

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