Magnetic effect of current practice · Mixed difficulty

The oscillating magnetic field in a plane electromagnetic wave is given by $B_y=5 \times 10^{-6} \sin 1000 \pi\left(5 x-4 \times 10^8 t\right) \mathrm{T}$ The amplitude of electric field will be:

The deflection in moving coil galvanometer falls from 25 divisions to 5 division when a shunt of $24\, \Omega$ is applied. The resistance of galvanometer coil will be :

Statement I: When radius of a circular wire carrying current is doubled, its magnetic moment becomes four times.
Statement II: Magnetic moment is directly proportional to area of the loop.
Which of the following statement(s) is/are correct?

$\oint {\overrightarrow B \cdot \overrightarrow {dl} } = {\mu _0}I$ is called as

The intensity of magnetic induction at the centre of a current – carrying circular coil is ${B_1}$ and at a point on its axis at a distance equal to its radius from the centre is ${B_2}$, then ${B_1}/{B_2}$ is

Assertion (A) The magnetic moment ( $\mu$ ) of an electron revolving around the nucleus decreases with increasing principle quantum number $(n)$.

Reason (R) Magnetic moment of the revolving electron, $\mu \propto {n}$

Current $i$ is flowing in a coil of area $A$ and number of turns $N$, then magnetic moment of the coil, $M$ is equal to

The magnetic induction at a point near end of a current carrying solenoid is $(I=$ current, $\mathbf{n}=$ number of turns per unit length, $\mu_0=$ permeability

To convert a voltmeter measuring 30 V into voltmeter measuring 330 V, if the resistance of the voltmeter is $1000\,\Omega ,$ the resistance to be connected in series is

Magnetic lines of force due to a current in a
circular conductor are _______

Assertion (A): If an electron is not deflected while passing through a certain region of space, then only possibility is that there is no magnetic field in this region.

Reason (R): Force on an electron moving in a magnetic field is directly proportional to the magnetic field applied.

Magnetic field at any point on the axis of a current element is

A galvanometer of resistance $100\,\Omega$ gives a full scale deflection for a current of ${10^{ - 5}}A$. To convert it into a ammeter capable of measuring upto 1A, we should connect a resistance of

A long solenoid of length L has a mean
diameter D. It has n layers of windings of N
turns each. If it carries a current I, the
magnetic field at its centre will be

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

Assertion: A moving charged particle gets energy from magnetic field.
Reason: Magnetic force works on moving charged particle.

To convert a galvanometer into a voltmeter one should connect a

An electron of charge "$e$" has a time period of revolution of "$T$" in a Bohr orbit of radius "$r$". The dipole moment of the electron is

The resistance of ideal voltmeter is

The resistance of ideal voltmeter is

Statement-1: A charged particle can never move along a magnetic field line in absence of any other force.
Statement-2: Force due to magnetic field is given by $\overrightarrow{{F}}=q(\vec{v} \times \overrightarrow{{B}})$

Statement I - A bar magnet can exert torque on itself due to it's own field.

Statement II - One element of a current carrying wire can exert a force on another element of same wire.

The turns of a solenoid, designed to provide a given magnetic
flux density along its axis, are wound to fill the space between
two concentric cylinders of fixed radii. How should the diameter
$d$ of the wire used be chosen so as to minimize the heat
dissipated in the windings?

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 bar magnet is placed inside a uniform
magnetic field. What does it experience?

The current sensitivity of a galvanometer can be increased by :
(A) Decreasing the number of turns
(B) Increasing the magnetic field
(C) Decreasing the area of the coil
(D) Decreasing the torsional constant of the spring
Choose the most appropriate answer from the options given below :

An ideal coil of 10 henry is joined in series with a resistance of $5 \mathrm{ohm}$ and a battery of 5 volt. After two seconds joining, the current flowing in ampere in the circuit will be :-

Assertion (A): Torque on the coil is always maximum, when coil is suspended in a radial magnetic field.

Reason (R): Torque depends upon the magnitude of the applied magnetic field.

A tangent galvanometer has a coil of 25 turns and a radius of 15 cm. The horizontal component of the earth’s magnetic field is $3 \times {10^{ - 5}}$T. The current required to produce a deflection of 45$^ \circ$ in it is

A charge particle moving in magnetic field $B$, has the components of velocity along $B$ as well as perpendicular to $B$. The path of the charge particle will be