Bar Magnet(equivalent solenoid, magnetic field lines,... ) NEET Questions

Physics - Magnetic Effects of Current and Magnetism

Bar Magnet(equivalent solenoid, magnetic field lines,... ) MCQ Questions


13.
The equatorial field of a bar magnet with moment 3 A·m² at distance 20 cm is:
A.
3.75 × 10⁻⁵ T
B.
1.25 × 10⁻⁵ T
C.
1.875 × 10⁻⁴ T
D.
1.875 × 10⁻⁵ T
😑 View Answer Rough Work Error
ANSWER :
A. 3.75 × 10⁻⁵ T
14.
If the bar magnet is cut into two halves along its length (parallel to its length), each half has:
A.
Half pole strength, same length, half moment
B.
Half pole strength, same length, same moment
C.
Same pole strength, same length, half moment
D.
Zero magnetic moment
😑 View Answer Rough Work Error
ANSWER :
A. Half pole strength, same length, half moment
15.
If a bar magnet is cut into two halves perpendicular to its length (across its width), each half has:
A.
Same pole strength, same length, half moment
B.
Same pole strength, half length, half moment
C.
Half pole strength, half length, same moment
D.
Zero magnetic moment
😑 View Answer Rough Work Error
ANSWER :
B. Same pole strength, half length, half moment
16.
The field produced by a bar magnet is similar to that of:
A.
An electric dipole (with replacements: μ₀ ↔ 1/ε₀, m ↔ p)
B.
A current-carrying infinite wire
C.
A point charge
D.
A uniform electric field
😑 View Answer Rough Work Error
ANSWER :
A. An electric dipole (with replacements: μ₀ ↔ 1/ε₀, m ↔ p)
17.
Torque on a bar magnet of moment m placed in uniform magnetic field B at angle θ is:
A.
τ = m/B
B.
τ = mB sin θ (directed perpendicular to both m and B)
C.
τ = 0 always in uniform field
D.
τ = mB cos θ
😑 View Answer Rough Work Error
ANSWER :
B. τ = mB sin θ (directed perpendicular to both m and B)
18.
The torque on a bar magnet in uniform B is maximum when:
A.
m is perpendicular to B (θ = 90°)
B.
m is parallel to B
C.
B is zero
D.
m is antiparallel to B
😑 View Answer Rough Work Error
ANSWER :
A. m is perpendicular to B (θ = 90°)