Q35.Consider a long thin conducting wire carrying a uniform current I. A particle having mass " M " and charge " q " is released at a distance " a " from the wire with a speed v0 along the direction of current in the wire. The particle gets attracted to the wire due to magnetic force. The particle turns round when it is at distance x from the wire. The value of x is [ μ0 is vacuum permeability] (1) ae−4πmvoqμoI (2) a [1 − 2qμoImvo ] − 2 qμoI (3) a [1 mv ] (4) a
What This Question Tests
This complex problem asks for the minimum distance a charged particle approaches a current-carrying wire due to magnetic force, which changes the direction of velocity but does no work, requiring conservation of angular momentum and energy considerations.
Concepts Tested
Formulas Used
B = μ₀I / (2πr)
F = q(v x B)
Work done by magnetic force is zero
📚 NCERT Sections This Tests
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?
4.7 — 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.
4.5 — 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
- Magnetic force on a current-carrying wire, work-energy theorem in magnetic field
- Year
- 2025
- Shift
- 28 Jan Shift 1
- Q Number
- Q35
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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