Q14. Two long currents carrying thin wires, both with current I , are held by insulating threads of length L and are in equilibrium as shown in the figure, with threads making an angle ' θ ' with the vertical. If wires have a mass λ per unit length then the value of I is: ( g = gravitational acceleration) (1) (2) tanθ √πλgLμ0 sinθ√πλgLμ0 cosθ (3) (4) tanθ 2sinθ√πλgLμ0cosθ 2√πgLμ0
What This Question Tests
This question combines magnetic force between current-carrying wires with equilibrium under gravity and tension. It requires drawing a free-body diagram for one wire and resolving forces to find the current 'I'.
Concepts Tested
Formulas Used
F_magnetic = (μ₀ I₁ I₂ L) / (2πd)
mg = λLg
ΣF_x = 0
ΣF_y = 0
📚 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.
4.5 — 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?
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?
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Force between parallel currents, equilibrium of forces
- Year
- 2015
- Shift
- 04 Apr
- Q Number
- Q14
- Type
- Multi concept
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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