Q20.Currents of a 10 ampere and 2 ampere are passed through two parallel thin wires A and B respectively in opposite directions. Wire A is infinitely long and the length of the wire B is 2 m. The force acting on the conductor B, which is situated at 10 cm distance from A will be (1) 8 × 10−5 N (2) 5 × 10−5 N (3) 8π × 10−7 N (4) 4π × 10−7 N
What This Question Tests
This question tests the ability to calculate the magnetic field produced by an infinitely long current-carrying wire and then use that field to determine the force exerted on another parallel current-carrying wire.
Concepts Tested
Formulas Used
B = μ₀I / (2πr)
F = BIL
📚 NCERT Sections This Tests
4.7 — Two Long And Parallel Straight Wires A And B Carrying Currents Of
Physics Class 11 · Chapter 4
4.7 Two long and parallel straight wires A and B carrying currents of 8.0 A and 5.0 A in the same direction are separated by a distance of 4.0 cm. Estimate the force on a 10 cm section of wire A.
4.6 — A 3.0 Cm Wire Carrying A Current Of 10 A Is Placed Inside A Solenoid
Physics Class 11 · Chapter 4
4.6 A 3.0 cm wire carrying a current of 10 A is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 0.27 T. What is the magnetic force on the wire?
4.5 — What Is The Magnitude Of Magnetic Force Per Unit Length On A Wire
Physics Class 11 · Chapter 4
4.5 What is the magnitude of magnetic force per unit length on a wire carrying a current of 8 A and making an angle of 30º with the direction of a uniform magnetic field of 0.15 T?
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Force between parallel current-carrying wires
- Year
- 2012
- Shift
- 26 May Online
- Q Number
- Q20
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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