- 1(current)
Q. No.Two infinitely long parallel conducting wires \(A\) and \(B\) carry currents \(I\) and \(2I,\) respectively, in the same direction. The wire \(A\) has a uniform mass per unit length \(\lambda\) and lies on an insulated floor. The wire \(B\) is kept fixed at a height \(h\) above the floor. The minimum magnitude of \(h\) so that the wire \(A\) does not rise from the floor is:
1. \( \dfrac{4\mu_0 I^2}{\pi \lambda g} \)
2. \( \dfrac{\mu_0 I^2}{2\pi \lambda g} \)
3. \( \dfrac{\mu_0 I^2}{\pi \lambda g} \)
4. \( \dfrac{2\mu_0 I^2}{\pi \lambda g} \)
1. \( \dfrac{4\mu_0 I^2}{\pi \lambda g} \)
2. \( \dfrac{\mu_0 I^2}{2\pi \lambda g} \)
3. \( \dfrac{\mu_0 I^2}{\pi \lambda g} \)
4. \( \dfrac{2\mu_0 I^2}{\pi \lambda g} \)
Subtopic: Â Force between Current Carrying Wires |
 53%
Level 3: 35%-60%
NEET - 2026
Please attempt this question first.
Hints
Please attempt this question first.
Two very long, straight, parallel conductor \(\mathrm{A}\) and \(\mathrm{B}\) carry current of \(5~\text{A}\) and \(10~\text{A}\) respectively and are at a distance of \(10~\mathrm{cm}\) from each other. The direction of the current in the two conductors is the same. The force acting per unit length between two conductors is:
(\(\mu_0=4\pi \times 10^{-7}\) SI unit)
(\(\mu_0=4\pi \times 10^{-7}\) SI unit)
| 1. | \(2\times10^{-4}~\text{Nm}^{-1}\) and is attractive |
| 2. | \(2\times10^{-4}~\text{Nm}^{-1}\) and is repulsive |
| 3. | \(1\times10^{-4}~\text{Nm}^{-1}\) and is attractive |
| 4. | \(1\times10^{-4}~\text{Nm}^{-1}\) and is repulsive |
Subtopic: Â Force between Current Carrying Wires |
 76%
Level 2: 60%+
NEET - 2022
Hints
An arrangement of three parallel straight wires placed perpendicular to the plane of paper carrying the same current in the same direction is shown in the figure. The magnitude of force per unit length on the middle wire \(B\) is given by:
| 1. | \(\dfrac{\mu_0i^2}{2\pi d}\) | 2. | \(\dfrac{2\mu_0i^2}{\pi d}\) |
| 3. | \(\dfrac{\sqrt{2}\mu_0i^2}{\pi d}\) | 4. | \(\dfrac{\mu_0i^2}{\sqrt{2}\pi d}\) |
Subtopic: Â Force between Current Carrying Wires |
 67%
Level 2: 60%+
NEET - 2017
Hints
Links
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 |
 86%
Level 1: 80%+
AIPMT - 1998
Hints
- 1(current)
Q. No.
© 2026 GoodEd Technologies Pvt. Ltd.