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. | \(4~\text{T}\) |
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 particle of charge +q and mass m moving under the influence of a uniform electric field and a uniform magnetic field follows a trajectory from P to Q as shown in the figure. The velocities at P and Q are and respectively. Which of the following statement(s) is/are correct?
1. | \(\mathrm{E}=\frac{3}{4} \frac{\mathrm{mv}^2}{\mathrm{qa}}\) |
2. | Rate of work done by electric field at P is\(\frac{3}{4} \frac{\mathrm{mv}^3}{\mathrm{a}}\) |
3. | Rate of work done by both fields at Q is zero |
4. | All of the above |
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. |
A current-carrying wire is placed in a uniform magnetic field in the shape of the curve \(y= \alpha sin ({\pi x \over L}),~0 \underline{<}x \underline{<}~2L\)
. What will be the force acting on the wire?
1. | \(iBL \over \pi\) | 2. | \(iBL \pi\) |
3. | \(2iBL \) | 4. | Zero |
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 particle with charge q, moving with a momentum p, enters a uniform magnetic field normally. The magnetic field has magnitude B and is confined to a region of width d, where . The particle is deflected by an angle in crossing the field, then:
1. | \(\sin \theta={Bqd \over p}\) | 2. | \(\sin \theta={p \over Bqd}\) |
3. | \(\sin \theta={Bp \over qd}\) | 4. | \(\sin \theta={pd \over Bq}\) |
A neutron, a proton, an electron and an \(\alpha\text-\)particle enter a region of the uniform magnetic field with the same velocity. The magnetic field is perpendicular and directed into the plane of the paper. The tracks of the particles are labelled in the figure.
Which track will the \(\alpha\text-\)particle follow?
1. | \(A\) | 2. | \(B\) |
3. | \(C\) | 4. | \(D\) |
A charged particle is projected through a region in a gravity-free space. If it passes through the region with constant speed, then the region may have:
1. \(\vec{E}=0, \vec{B} \neq 0\)
2. \(\vec{E} \neq 0, \vec{B} \neq 0\)
3. \(\vec{E} \neq 0, \vec{B}=0\)
4. Both (1) & (2)
A particle having a mass of carries a charge of The particle is given an initial horizontal velocity of in the presence of an electric field and magnetic field . How can we keep the particles moving in a horizontal direction?
a. | should be perpendicular to the direction of velocity and should be along the direction of velocity. |
b. | Both and should be along the direction of velocity. |
c. | Both and are mutually perpendicular and perpendicular to the direction of velocity. |
d. | should be along the direction of velocity and 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