- 1(current)
Q. No.Two long parallel wires are at a distance of \(1\) m. If both of them carry one ampere of current in the same direction, then the force of attraction on the unit length of the wires will be:
1. \(2\times10^{-7}\) N/m
2. \(4\times10^{-7}\) N/m
3. \(8\times10^{-7}\) N/m
4. \(10^{-7}\) N/m
Subtopic: Â Force between Current Carrying Wires |
 85%
Level 1: 80%+
AIPMT - 1998
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Two long conductors, separated by a distance \(d,\) carry currents \(I_1\)​ and \(I_2\)​ in the same direction, exerting a force \(F\) on each other. Now, the current in one of the conductors is doubled and its direction is reversed, while the separation distance between the conductors is increased to \(3d.\) What is the new force between the conductors?
1. \(-2F\)
2. \(F/3\)
3. \(-2F/3\)
4. \(-F/3\)
1. \(-2F\)
2. \(F/3\)
3. \(-2F/3\)
4. \(-F/3\)
Subtopic: Â Force between Current Carrying Wires |
 86%
Level 1: 80%+
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Two parallel infinite wires carry equal currents as shown. If both the currents are doubled and separation is halved, the force on a \(10~\text{cm}\) section of one of the wires becomes:
| 1. | \(4\) times | 2. | \(\dfrac{1}{4}\) times |
| 3. | \(8\) times | 4. | \(\dfrac{1}{8}\) times |
Subtopic: Â Force between Current Carrying Wires |
 83%
Level 1: 80%+
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Two very long wires of length \(L\) are placed parallel to each other separated by a distance \(r(r << L) . \) The wires carry equal currents \(i .\) The force between the two wires is nearly:
| 1. | \(\dfrac{\mu_{0} i^{2} L}{2 \pi r}\) | 2. | \(\dfrac{\mu_{0} i^{2} L}{4 \pi r}\) |
| 3. | \(\dfrac{\mu_{0} i^{2} L}{2 r}\) | 4. | \(\dfrac{\mu_{0} i^{2} L}{4 r}\) |
Subtopic: Â Force between Current Carrying Wires |
 84%
Level 1: 80%+
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Consider the situation shown in the figure. The straight wire is fixed but the loop can move under magnetic force. The loop will:
| 1. | remain stationary |
| 2. | move towards the wire |
| 3. | move away from the wire |
| 4. | rotate about the wire |
Subtopic: Â Force between Current Carrying Wires |
 80%
Level 1: 80%+
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Two long, thin, parallel conductors are separated by a distance \(d\) and carry currents \(i_1\)​ and \(i_2,\) respectively. The force per unit length \(F\) acting on one conductor is analysed under the following conditions:
| (A) | The force \(F\) is attractive, if \(i_1\) and \(i_2\) flow in the same direction. |
| (B) | The force \(F\) is attractive, if \(i_1\) and \(i_2\) flow in opposite directions. |
| (C) | The magnitude of the force \(F\) is the same for both conductors. |
| (D) | The magnitude of the force \(F\) is different for the two conductors. |
Choose the correct option from the options given below:
| 1. | (A) and (C) only |
| 2. | (A) and (B) only |
| 3. | (B) and (D) only |
| 4. | (B), (C) and (D) only |
Subtopic: Â Force between Current Carrying Wires |
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Level 2: 60%+
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Two long parallel wires, separated by a distance of \(4\) cm, carry currents of \(2\) A and \(6\) A in the same direction. The force per metre of wire length acting between the wires is:
| 1. | \(4\times 10^{-5}~\text{N/m}\) | 2. | \(6\times 10^{-5}~\text{N/m}\) |
| 3. | \(6\times 10^{-6}~\text{N/m}\) | 4. | \(6\times 10^{-4}~\text{N/m}\) |
Subtopic: Â Force between Current Carrying Wires |
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Level 2: 60%+
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- 1(current)
Q. No.
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