In a uniform magnetic field of \(0.049~\text T\), a magnetic needle performs \(20\) complete oscillations in \(5\) seconds as shown. The moment of inertia of the needle is \(9.8 × 10^{-6} ~\text{kg m}^2\). If the magnitude of magnetic moment of the needle is \(x \times 10^{-5 }~\text {Am}^2;\) then the value of '\(x\)' is:
1. \(128\pi^2\) 2. \(50\pi^2\)
3. \(1280\pi^2\) 4. \(5\pi^2\)
Subtopic:  Bar Magnet |
 53%
Level 3: 35%-60%
NEET - 2024
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Match List-I with List-II.
List-I
Material
List-II
Susceptibility \((\chi)\)
\(\mathrm{(A)}\) Diamagnetic \(\mathrm{(I)}\) \(\chi=0\)
\(\mathrm{(B)}\) Ferromagnetic \(\mathrm{(II)}\) \(0>\chi\geq-1\)
\(\mathrm{(C)}\) Paramagnetic \(\mathrm{(III)}\) \(\chi\gg1\)
\(\mathrm{(D)}\) Non-magnetic \(\mathrm{(IV)}\) \(0<\chi<\varepsilon\) (a small positive number)
Choose the correct answer from the options given below:
1. \(\text{A-II, B-I, C-III, D-IV}\) 2. \(\text{A-III, B-II, C-I, D-IV}\)
3. \(\text{A-IV, B-III, C-II, D-I}\) 4. \(\text{A-II, B-III, C-IV, D-I}\)
Subtopic:  Magnetic Materials |
 69%
Level 2: 60%+
NEET - 2024
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A sheet is placed on a horizontal surface in front of a strong magnetic pole. A force is needed to:
A. hold the sheet there if it is magnetic.
B. hold the sheet there if it is non-magnetic.
C. move the sheet away from the pole with uniform velocity if it is conducting.
D. move the sheet away from the pole with uniform velocity if it is both, non-conducting and non-polar.
Choose the correct statement\((\mathrm s )\) from the options given below:
1. A and C only 2. A, C and D only
3. C only 4. B and D only
Subtopic:  Magnetic Materials |
 55%
Level 3: 35%-60%
NEET - 2024
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An iron bar of length \( L\) has a magnetic moment \(M.\) It is bent at the middle of its length such that the two arms make an angle \(60^\circ\) with each other. The magnetic moment of this new magnet is:
1. \(\dfrac{M}{2}\) 2. \({2 M}\)
3. \(\dfrac{{M}}{\sqrt{3}}\) 4. \(M\)
Subtopic:  Bar Magnet |
 54%
Level 3: 35%-60%
NEET - 2024
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The length of a magnetized iron bar is \(L\) and its magnetic moment is \(M.\) When this bar is bent to form a semicircle its magnetic moment is:
1. \(M\) 2. \(\dfrac{M\pi}{2}\)
3. \( \dfrac{M}{2\pi}\) 4. \(\dfrac{2M}{\pi}\)
Subtopic:  Bar Magnet |
 75%
Level 2: 60%+
NEET - 2024
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Match List-I with List-II 
List-I (Material) List-II (Example)
(A) Diamagnet (I) Alnico
(B) Paramagnet (II) Copper
(C) Soft ferromagnet (III) Aluminium
(D) Hard ferromagnet (IV) Gadolinium
Choose the correct answer from the options given below:
1. A-I, B-II, C-III, D-IV 2. A-IV, B-III, C-II, D-I
3. A-III, B-II, C-I, D-IV 4. A-II, B-III, C-IV, D-I
Subtopic:  Magnetic Materials |
 59%
Level 3: 35%-60%
NEET - 2024
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The best suited curve showing the variations of susceptibility (\(\chi\)) of a paramagnetic material in free space with temperature (\(T\)) is: 
1.   2.
3. 4.
Subtopic:  Magnetic Materials |
 84%
Level 1: 80%+
NEET - 2024
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The net magnetic flux through any closed surface is:
1. negative 2. zero
3. positive 4. infinity
Subtopic:  Analogy between Electrostatics & Magnetostatics |
 87%
Level 1: 80%+
NEET - 2023
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The variation of susceptibility \((\chi)\) with absolute temperature \((T)\) for a paramagnetic material is represented as:
1. 2.
3. 4.
 60%
Level 2: 60%+
NEET - 2023
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Given below are two statements:
Assertion (A): Gauss's law for magnetism states that the net magnetic flux through any closed surface is zero.
Reason (R): The magnetic monopoles do not exist. North and South poles occur in pairs, allowing vanishing net magnetic flux through the surface.
 
1. (A) is True but (R) is False.
2. (A) is False but (R) is True.
3. Both (A) and (R) are True and (R) is the correct explanation of (A).
4. Both (A) and (R) are True but (R) is not the correct explanation of (A).
Subtopic:  Analogy between Electrostatics & Magnetostatics |
 76%
Level 2: 60%+
NEET - 2022
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