A square current-carrying loop is suspended in a uniform magnetic field acting in the plane of the loop. If the force on one arm of the loop is \( \overrightarrow{F}\), what will be the net force on the remaining three arms of the loop?
1. | \(3 \overrightarrow{F}\) | 2. | \(- \overrightarrow{F}\) |
3. | \(-3 \overrightarrow{F}\) | 4. | \( \overrightarrow{F}\) |
1. | 8 N in - z-direction. |
2. | 4 N in the z-direction. |
3. | 8 N in the y-direction. |
4. | 8 N in the z-direction. |
A closed-loop PQRS carrying a current is placed in a uniform magnetic field. If the magnetic forces on segments PS, SR, and RQ are F1, F2, and F3 respectively, and are in the plane of the paper and along the directions shown,
then which of the following forces acts on the segment QP?
1.
2.
3.
4.
A particle of mass \(m\), charge \(Q\), and kinetic energy \(T\) enters a transverse uniform magnetic field of induction \(\vec B\). What will be the kinetic energy of the particle after seconds?
1. | \(3~\text{T}\) | 2. | \(2~\text{T}\) |
3. | \(\text{T}\) | 4. | \(4~\text{T}\) |
A beam of electrons passes un-deflected through mutually perpendicular electric and magnetic fields. Where do the electrons move if the electric field is switched off and the same magnetic field is maintained?
1. | in an elliptical orbit. |
2. | in a circular orbit. |
3. | along a parabolic path. |
4. | along a straight line. |
Two identical long conducting wires \(\mathrm{AOB}\) and \(\mathrm{COD}\) are placed at a right angle to each other, with one above the other such that '\(O\)' is the common point for the two. The wires carry \(I_1\) and \(I_2\) currents, respectively.
Point '\(P\)' is lying at a distance '\(d\)' from '\(O\)' along a direction perpendicular to the plane containing the wires. What will be the magnetic field at the point \(P\)?
1. \(\frac{\mu_0}{2\pi d}\left(\frac{I_1}{I_2}\right )\)
2. \(\frac{\mu_0}{2\pi d}\left[I_1+I_2\right ]\)
3. \(\frac{\mu_0}{2\pi d}\left[I^2_1+I^2_2\right ]\)
4. \(\frac{\mu_0}{2\pi d}\sqrt{\left[I^2_1+I^2_2\right ]}\)
1. | \(7.14\) A | 2. | \(5.98\) A |
3. | \(14.76\) A | 4. | \(11.32\) A |
An electron is moving in a circular path under the influence of a transverse magnetic field of \(3.57\times 10^{-2}~\text{T}\). If the value of \(\frac{e}{m}\) is \(1.76\times 10^{11}~\text{C/kg}\), what will be the frequency of revolution of the electron?
1. | \(1~\text{GHz}\) | 2. | \(100~\text{MHz}\) |
3. | \(62.8~\text{MHz}\) | 4. | \(6.28~\text{MHz}\) |
A rectangular loop carrying a current \(\mathrm{I_1}\), is situated near a long straight wire carrying a steady current \(\mathrm{I_2}\).
If the wire is parallel to one of the sides of the loop and is in the plane of the loop as shown in the figure, then the current loop will:
1. | move away from the wire. |
2. | move towards the wire. |
3. | remain stationary. |
4. | rotate about an axis parallel to the wire. |
When will the current sensitivity of a moving coil galvanometer be high?
(N = number of turns, B = magnetic field, A = area of coil, and C = Torsional constant of spring)
1. | N is small | 2. | B is small |
3. | A is small | 4. | C is small |