Column I gives certain situations in which a straight metallic wire of resistance is used and Column II gives some resulting effects. Match the statements in Column I with the statements in Column II and indicate your answer by darkening appropriate bubbles in the 4 × 4 matrix given in the ORS.
← IIT-JEE 2007 · Paper 1
PhysicsMatrix match+6Question 21 of 66
IIT-JEE 2007 · Paper 1, Physics question 21
Column I
- AA charged capacitor is connected to the ends of the wire
- BThe wire is moved perpendicular to its length with a constant velocity in a uniform magnetic field perpendicular to the plane of motion
- CThe wire is placed in a constant electric field that has a direction along the length of the wire
- DA battery of constant emf is connected to the ends of the wire
Column II
- PA constant current flows through the wire
- QThermal energy is generated in the wire
- RA constant potential difference develops between the ends of the wire
- SCharges of constant magnitude appear at the ends of the wire
| P | Q | R | S | |
|---|---|---|---|---|
| A | ||||
| B | ||||
| C | ||||
| D |
Answer and worked solution
Official answer: A → Q; B → R, S; C → S; D → P, Q, R
- A, capacitor across the wire: it discharges; the current decays (not constant), and heat is produced. → Q.
- B, wire moving through a field: a motional emf separates charges until a constant potential difference exists, with constant charges at the ends; no steady current flows in the isolated wire. → R, S.
- C, wire in a field along its length: charges move until the induced charges at the ends cancel the field inside; then nothing flows, and the ends keep constant charges. → S. (The potential difference along the conductor becomes zero.)
- D, battery: a constant current, Joule heating, and a constant potential difference. → P, Q, R.
Answer: A → Q; B → R, S; C → S; D → P, Q, R