Two toroids \(1\) and \(2\) have total no. of turns \(200\) and \(100\) respectively with average radii \(40~\text{cm}\) and \(20~\text{cm}\) respectively. If they carry the same current \(i,\) what will be the ratio of the magnetic fields along the two loops?
1. \(1:1\)
2. \(4:1\)
3. \(2:1\)
4. \(1:2\)

Subtopic:  Ampere Circuital Law |
 80%
Level 1: 80%+
NEET - 2019
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Three infinitely long conductors carrying currents \(I_1, I_2~\text{and}~I_3\) lie perpendicular to the plane of the paper as shown below.

                                    

If the value of the integral \(\oint \vec {B}.\vec {dl}\) for the loops \(C_1, C_2,~\text{and}~C_3\) are \(2\mu_0, 4\mu_0~\text{and}~\mu_0\) in the units of N/A, respectively, then:
1. \(I_1=3 A\)  into the paper 2. \(I_2=3 A\) out of the paper
3. \(I_3=0\) 4. \(I_3=1 A\) out of the paper
Subtopic:  Ampere Circuital Law |
 50%
Level 3: 35%-60%
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A ring of radius \(R\) carries a linear charge density \(\lambda\). It is rotating with angular speed \(\omega\) about an axis passing through the centre and perpendicular to the plane. What is the magnetic field at its centre?

1. \(\dfrac{3 \mu_{0} \lambda \omega}{2}\) 2. \(\dfrac{\mu_{0} \lambda \omega}{2}\)
3. \(\dfrac{\mu_{0} \lambda \omega}{\pi}\) 4. \(\mu_{0} \lambda \omega\)
Subtopic:  Magnetic Field due to various cases |
 74%
Level 2: 60%+
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The figure depicts a cross-section of a large metal sheet with an electric current flowing along its surface. The current in a \(dl\)-width strip is (\(Kdl\)), where \(K\) is a constant. What is the magnetic field at a point \(P\) and at a distance \(x\) from the metal strips?
         
1. \(\frac{1}{2} \mu_{0} K x\)
2. \(\mu_{0} K\)
3. \(\frac{1}{2} \mu_{0} K\)
4. \(\frac{\mu_{0} K x}{4}\) 
Subtopic:  Ampere Circuital Law |
Level 3: 35%-60%
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A galvanometer having a resistance of \(8\) ohms is shunted by a wire of resistance of \(2\) ohms. If the total current is \(1~\text{A},\) the part of it passing through the shunt will be:
1. \(0.25~\text{A}\)
2. \(0.8~\text{A}\)
3. \(0.2~\text{A}\)
4. \(0.5~\text{A}\)
Subtopic:  Conversion to Ammeter & Voltmeter |
 71%
Level 2: 60%+
PMT - 1998
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The current sensitivity of a moving coil galvanometer is \(5\) div/mA and its voltage sensitivity (angular deflection per unit voltage applied) is \(20\) div/V. How much is the resistance of the galvanometer?
1. \(40~ \Omega\) 2. \(25~ \Omega\)
3. \(250~ \Omega\) 4. \(500~ \Omega\)
Subtopic:  Moving Coil Galvanometer |
 75%
Level 2: 60%+
NEET - 2018
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Perpendicularly, an electron and a proton enter a magnetic field. Both have the same amount of kinetic energy. Which of the following statements is correct?

1. Trajectory of electron is less curved
2. Trajectory of proton is less curved
3. Both trajectories are equally curved
4. Both move on a straight-line path

Subtopic:  Lorentz Force |
 52%
Level 3: 35%-60%
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A particle having a mass of \(10^{-2}~\text{kg}\) carries a charge of \(5\times 10^{-8}~\text{C}.\) The particle is given an initial horizontal velocity of \(10^{5}~\text{ms}^{-1}\) in the presence of an electric field \(\vec{E}\) and magnetic field \(\vec{B}.\) How can we keep the particles moving in a horizontal direction?
a. \(\vec{B}\) should be perpendicular to the direction of velocity and \(\vec{E}\) should be along the direction of velocity.
b. Both \(\vec{B}\) and \(\vec{E}\) should be along the direction of velocity.
c. Both \(\vec{B}\) and \(\vec{E}\) are mutually perpendicular and perpendicular to the direction of velocity.
d. \(\vec{B}\) should be along the direction of velocity and \(\vec{E}\) should be perpendicular to the direction of velocity.

Which one of the following pairs of statements are possible?
1. (a) and (c)
2. (c) and (d)
3. (b) and (c)
4. (b) and (d)

Subtopic:  Lorentz Force |
 60%
Level 2: 60%+
NEET - 2010
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A long solenoid has \(800\) turns per metre of the length of the solenoid. A current of \(1.6\) A flows through it. What is the magnetic induction at the end of the solenoid on its axis?
1. \(16 \times 10^{-4}~\text{T}\) 2. \(8 \times 10^{-4}~\text{T}\)
3. \(32 \times 10^{-4}~\text{T}\) 4. \(4 \times 10^{-4}~\text{T}\)
Subtopic:  Ampere Circuital Law |
 66%
Level 2: 60%+
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A cell is connected between the points \(A\) and \(C\) of a circular conductor \(ABCD\) of centre \(O\) with an angle of \(AOC = 60^{\circ}.\)
If \(B_1\) and \(B_2\) are the magnitudes of the magnetic fields at \(O\) due to the currents in \(ABC\) and \(ADC\) respectively, the ratio \(B_1:B_2\) will be:
1. \(0.2\) 2. \(6\)
3. \(1\) 4. \(5\)
Subtopic:  Magnetic Field due to various cases |
 56%
Level 3: 35%-60%
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