- 1(current)
Q. No.A helmholtz coil has a pair of loops, each with \(N\) turns and radius \(R.\) They are placed coaxially at a distance \(R\) and the same current \(I\) flows through the loops in the same direction. The magnitude of the magnetic field at the point \(P,\) midway between the centres \(A\) and \(C,\) is given by:
1. \(\dfrac{8N\mu_0I}{5^{1/2}R}\)
2. \(\dfrac{4N\mu_0I}{5^{3/2}R}\)
3. \(\dfrac{4N\mu_0I}{5^{1/2}R}\)
4. \(\dfrac{8N\mu_0I}{5^{3/2}R}\)
1. \(\dfrac{8N\mu_0I}{5^{1/2}R}\)
2. \(\dfrac{4N\mu_0I}{5^{3/2}R}\)
3. \(\dfrac{4N\mu_0I}{5^{1/2}R}\)
4. \(\dfrac{8N\mu_0I}{5^{3/2}R}\)
Subtopic: Biot-Savart Law |
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Level 2: 60%+
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A thin ring of \(10~\text{cm}\) radius carries a uniformly distributed charge. The ring rotates at a constant angular speed of \(40\pi ~\text{rad}~\text{s}^{-1}\) about its axis, perpendicular to its plane. If the magnetic field at its centre is \(3.8\times 10^{-9}~\text{T},\) then the charge carried by the ring is close to:
(\(\mu_0=4\pi\times 10^{-7}~\text{N/A}^2\))
1. \(7\times 10^{-6}~\text{C}\)
2. \(4\times 10^{-5}~\text{C}\)
3. \(2\times 10^{-6}~\text{C}\)
4. \(3\times 10^{-5}~\text{C}\)
Subtopic: Biot-Savart Law |
59%
Level 3: 35%-60%
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A current loop, having two circular arcs joined by two radial lines is shown in the figure. It carries a current of \(10~\text{A}.\) The magnetic field at a point \({O}\) will be close to:
1. \(1.0\times 10^{-7}~\text{T}\)
2. \(1.5\times 10^{-7}~\text{T}\)
3. \(1.5\times 10^{-5}~\text{T}\)
4. \(1.0\times 10^{-5}~\text{T}\)
1. \(1.0\times 10^{-7}~\text{T}\)
2. \(1.5\times 10^{-7}~\text{T}\)
3. \(1.5\times 10^{-5}~\text{T}\)
4. \(1.0\times 10^{-5}~\text{T}\)
Subtopic: Biot-Savart Law |
56%
Level 3: 35%-60%
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Match List-I with List-II.
Choose the most appropriate answer from the options given below:
| List-I | List-II | ||
| (a) | Magnetic Induction | (i) | \({ML}^2{T}^{-2}{A}^{-1}\) |
| (b) | Magnetic Flux | (ii) | \({M}^0{L}^{-1}{A}\) |
| (c) | Magnetic Permeability | (iii) | \({MT}^{-2}{A}^{-1}\) |
| (d) | Magnetization | (iv) | \({MLT}^{-2}{A}^{-2}\) |
| 1. | (a) – (ii), (b) – (iv), (c) – (i), (d) – (iii) |
| 2. | (a) – (iii), (b) – (ii), (c) – (iv), (d) – (i) |
| 3. | (a) – (ii), (b) – (i), (c) – (iv), (d) – (iii) |
| 4. | (a) – (iii), (b) – (i), (c) – (iv), (d) – (ii) |
Subtopic: Biot-Savart Law |
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Two parallel long current-carrying wires separated by a distance \(2r\) are shown in the figure. The ratio of the magnetic field at \(A\) to the magnetic field produced at C is \(\dfrac{x}{7}.\) The value of \(x\) is
1. \(18\)
2. \(3\)
3. \(5\)
4. \(12\)
1. \(18\)
2. \(3\)
3. \(5\)
4. \(12\)
Subtopic: Biot-Savart Law |
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A square loop of edge length \(2~\text m\) carrying a current of \(2~\text A\) is placed with its edges parallel to the \(x-y \) axis. A magnetic field is passing through the \(x-y\) plane and expressed as
1. \(140~\text N\)
2. \(160~\text N\)
3. \(200~\text N\)
4. \(190~\text N\)
1. \(140~\text N\)
2. \(160~\text N\)
3. \(200~\text N\)
4. \(190~\text N\)
Subtopic: Biot-Savart Law |
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- 1(current)
Q. No.
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