The universal property of all substances is:
1. diamagnetism only
2. ferromagnetism only
3. paramagnetism only
4. both paramagnetism and diamagnetism

Subtopic:  Magnetic Materials |
 72%
Level 2: 60%+
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When a small ferromagnetic magnet is fully demagnetized, its coercivity is measured to be \(3\times 10^{3}~\text{Am}^{-1}. \) A solenoid of length \(10~\text{cm},\) consisting of \(100\) turns, is used to achieve this demagnetization. What should be the current flowing through the solenoid to completely demagnetize the magnet when placed inside it?
1. \(6~\text{A}\) 2. \(30~\text{mA}\)
3. \(3~\text{A}\) 4. \(1.5~\text{A}\)
Subtopic:  Magnetization & Magnetic Intensity |
 71%
Level 2: 60%+
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If the work done in turning a magnet of magnetic moment \(M\) by an angle of \(90^\circ\) from magnetic meridian is \(n\) times the corresponding work done to turn it through an angle of \(60^\circ,\) then the value of \(n\) is:
1. \(1\over 2\)
2. \(2\)
3. \(\sqrt 3\over 2\)
4. \(2\over \sqrt 3\)
Subtopic:  Analogy between Electrostatics & Magnetostatics |
 74%
Level 2: 60%+
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The relationship between permeability \(\mu\) and the magnetising field \(H\) for a sample of iron is given by \(\mu=\left(\dfrac{0.5}{H}+8\times10^{-4} \right)\text{ henry per metre},\) where \(H\) is measured in \(\text{A/m}.\) What value of \(H\) is required to produce a magnetic induction of \(1.0\text{ Wb/m}^2 \text{?}\)
1. \(500\text{ A/m}\) 2. \(0.625\text{ A/m}\)
3. \(625\text{ A/m}\) 4. \(5.25\text{ A/m}\)
Subtopic:  Magnetization & Magnetic Intensity |
 67%
Level 2: 60%+
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The susceptibility of a paramagnetic material is \(99.\) The permeability of the material in \(\text{Wb/A-m}\) is: 
(Permeability of free space, \(\mu_{0}=4\pi \times 10^{-7} \text{ Wb/A-m}\))
1. \(4 \pi \times 10^{-7} \)
2. \( 4 \pi \times 10^{-4} \)
3. \( 4 \pi \times 10^{-5} \)
4. \( 4 \pi \times 10^{-6} \)
Subtopic:  Magnetic Materials |
 88%
Level 1: 80%+
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A bar magnet having a magnetic moment of \(2.0\times10^{5}~\text{JT}^{-1}\) is placed along the direction of the uniform magnetic field of magnitude, \(B=14\times10^{-5}~\text{T}\). The work done in rotating the magnet slowly through \(60^\circ \) from the direction of the field is:
1. \(14~\text{J}\)
2. \(8.4~\text{J}\)
3. \(4~\text{J}\)
4. \(1.4~\text{J}\)
Subtopic:  Bar Magnet |
 91%
Level 1: 80%+
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Given below are two statements: 
Statement I: All paramagnetic substances become diamagnetic as their temperature is lowered.
Statement II: All ferromagnetic substances become paramagnetic when their temperature is lowered.
1. Statement I is incorrect and Statement II is correct.
2. Both Statement I and Statement II are correct.
3. Both Statement I and Statement II are incorrect.
4. Statement I is correct and Statement II is incorrect.
 59%
Level 3: 35%-60%
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A bar magnet of the magnetic moment \(M\) is placed at right angles to a magnetic induction \(B.\) If a force \(F\) is experienced by each pole of the magnet, the length of the magnet will be:
1. \(\dfrac{MB}{F}\) 2. \(\dfrac{BF}{M}\)
3. \(\dfrac{MF}{B}\) 4. \(\dfrac{F}{MB}\)
Subtopic:  Bar Magnet |
 75%
Level 2: 60%+
NEET - 2013
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If a magnetic monopole were to exist, what would be appropriate units of its ‘strength’?
1. \(\text{Wb}/\text{T}\)
2. \(\text{T}/\text{m}^3\)
3. \(\text{C.m}/\text{s}\)
4. \(\text{D}/\text{T}\)
Subtopic:  Analogy between Electrostatics & Magnetostatics |
 51%
Level 3: 35%-60%
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Given below are two statements: 
Assertion (A): Magnetic susceptibility is a pure number.
Reason (R): The value of magnetic susceptibility for vacuum is one.
 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.
Subtopic:  Magnetic Materials |
Level 3: 35%-60%
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