A wire of length \(L\) meters carrying a current of \(I\) ampere is bent in the form of a circle. What is its magnetic moment?
1. \( \dfrac{{IL}^2}{4} ~\text{A}\text-\text{m}^2 \) 2. \( \dfrac{{I} \times \pi {L}^2}{4} ~\text{A}\text-\text{m}^2 \)
3. \( \dfrac{2 {IL}^2}{\pi}~\text{A}\text-\text{m}^2 \) 4. \( \dfrac{{IL}^2}{4 \pi}~\text{A}\text-\text{m}^2 \)
Subtopic:  Magnetic Moment |
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Level 2: 60%+
NEET - 2020
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A uniform conducting wire of length \(12a\) and resistance '\(R\)' is wound up as a current-carrying coil in the shape of;

(i) an equilateral triangle of side '\(a\)'
(ii) a square of side '\(a\)'

The magnetic dipole moments of the coil in each case respectively are:
1. \(3Ia^2~\text{and}~4Ia^2\)
2. \(4Ia^2~\text{and}~3Ia^2\)
3. \(\sqrt{3}Ia^2~\text{and}~3Ia^2\)
4. \(3Ia^2~\text{and}~Ia^2\)

Subtopic:  Magnetic Moment |
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NEET - 2021
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The ratio of the radii of two circular coils is \(1:2.\) The ratio of currents in the respective coils such that the same magnetic moment is produced at the centre of each coil is:

1. \(4:1\) 2. \(2:1\)
3. \(1:2\) 4. \(1:4\)
Subtopic:  Magnetic Moment |
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Level 2: 60%+
NEET - 2022
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A magnetized wire of magnetic moment \(M\) and length \(L\) is bent in the form of the semi-circle of radius \(r\). The new magnetic moment is:
1. \(M\)
2. \(M / 2 \pi\)
3. \(M / \pi\)
4. \(2M / \pi\)
Subtopic:  Magnetic Moment |
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Level 3: 35%-60%
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A current-carrying wireframe is in the shape of digit eight \((8). \) It is carrying current \(i_0.\) If the radius of each loop is \(R_0,\) then the net magnetic dipole moment of the figure is: 
1. \(\left({{i}_{0}{\pi}{R}_{0}^{2}}\right)\sqrt{2} \) 2. zero
3. \({i}_{0}\times{2}{\pi}{R}_{0}^{2} \) 4. \({i}_{0}\left({{4}{\pi}{R}_{0}}\right) \)
Subtopic:  Magnetic Moment |
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Level 1: 80%+
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