Magnetic effect of current practice · Mixed difficulty

A charge moving with velocity v in x-direction
is subjected to a field of magnetic induction in
negative x-direction. As a result, the charge will

A thin circular disc of radius $R$ is uniformly charged with density $\sigma$. It rotates about its diameter with angular speed $\omega$. The magnetic moment of the disc is

The angle made by orbital angular momentum of electron with the direction of the orbital magnetic moment is

The direction of magnetic field at a point due
to an infinitely long wire carrying current is :

Two long and parallel straight wires $A$ and $B$ carrying current $5 \mathrm{~A}$ each in same direction. If the force on a $5 \mathrm{~cm}$ section of wire $B$ is $5 \times 10^{-6}$ $\mathrm{N}$, then the separation between two wires is ( $\mu_0=4 \pi \times 10^{-7}$ SI unit)

A galvanometer having 30 divisions has a current sensitivity of $20 \mu \mathrm{A} /$division. It has a resistance of $20\,\Omega$. How will you convert it into an ammeter measuring upto 1 ampere? How will you convert this ammeter into voltmeter reading upto 1 volt?

At what distance from a long straight wire carrying a current of $12 \mathrm{~A}$ will the magnetic field be equal to $3 \times 10^{-5} \mathrm{~Wb} / \mathrm{m}^2$ ?

Before using the tangent galvanometer, its coil
is set up in

A straight wire of mass $200 \mathrm{~g}$ and length $1.5 \mathrm{~m}$ carries a current of $2 \mathrm{~A}$. It is suspended in midair by a uniform horizontal magnetic field $B$. The magnitude of $B$ (in tesla) is (assume $\mathrm{g}=9.8 \mathrm{~ms}^{-2}$ )

A closely wound flat circular coil of 25 turns of wire has diameter of $10 \mathrm{~cm}$ which carries current of $4 \mathrm{~A}$, the flux density at the centre of a coil will be

Magnetic induction at the centre of a current carrying circular loop of area $\pi$ square metre is 0.2 Tesla. The magnetic moment of the loop is $\left(\mu_0\right.$ is the permeability of air)

The resistance of an ideal voltmeter is

The cyclotron assembly is filled with

The dominant force experienced by an electron
moving in a wire is

Force $\vec{F}$ experienced by a charger $q$ moving with a velocity $\vec{v}$ in an electric field of strength $\overrightarrow{\mathrm{E}}$ and a magnetic field of strength $\overrightarrow{\mathrm{B}}$ is:

A proton is revolving in a circular path with constant speed. Angle between angular momentum and magnetic dipole moment associated with it is

A charged particle moves along a circle under the action of possible constant electric and magnetic fields. Which of the following are possible?

A proton and an $\alpha -$ particle enter a uniform magnetic field perpendicularly with the same speed. If proton takes $25\,\mu$ second to make 5 revolutions, then the time period for the $\alpha -$ particle would be

A charge is fired through a magnetic field. The force acting on it is maximum when the direction of motion of the charge and magnetic field is

The magnetic dipole moment of a current loop
is independent of :

The AC voltage across a resistance can be measured using a :

The sensitivity of a tangent galvanometer is increased if

A cyclotron is used to accelerate protons $\left({ }_1^1 {H}\right)$ deuterons $\left({ }_1^2 \mathrm{H}\right)$ and $\alpha$-particles $\left({ }_2^4 \mathrm{He}\right)$. While exiting under similar conditions, the minimum $\mathrm{KE}$ is gained by :

The magnetic field is absent in which one of the
following physical situation?

If the acceleration and velocity of a charged particle moving in a constant magnetic region is given by $\mathbf{a}=a_1 \hat{\mathbf{i}}+a_2 \hat{\mathbf{k}}, \mathbf{v}=b_1 \hat{\mathbf{i}}+b_2 \hat{\mathbf{k}}$. $\left[a_1, a_2, b_1\right.$ and $b_2$ are constants], then choose the wrong statement.

Statement (I): A uniform electric field and a
uniform magnetic field are pointed in the same
direction. If an electron is projected in the same
direction the electron velocity will decrease in
magnitude.
Statement (II): Two infinite long parallel wires
are carrying current in the same direction. The
magnetic field at a point midway between the wires
is zero.
Statement (III): No net force acts on a rectangular
coil carrying a steady current when suspended in
a uniform magnetic field.
Which of the following is correct?

The magnitude of the magnetic field inside a
long solenoid is increased by

Assertion: A charge, whether stationary or in
motion produces a magnetic field around it
Reason: Moving charges produce only electric
field in the surrounding space.

The instantaneous acceleration of an electron in a magnetic field $\bar{B}=2 \bar{i}+3 \bar{j}+4 \bar{k}$ is $\bar{a}=x \bar{i}+\bar{j}-\bar{k}$. The magnitude of acceleration is

When a charge particle moving with velocity $\overrightarrow{\mathbf{v}}$ is subjected to a magnetic field of induction $\vec{B}$, the force on it is non-zero. This implies that