Magnetic effect of current practice · Mixed difficulty

A straight wire of diameter $0.5 \mathrm{~mm}$ carrying a current of $1 \mathrm{~A}$ is replaced by another wire of $1 \mathrm{~mm}$ diameter carrying the same current. The strength of the magnetic field far away is

A proton is projected with a uniform velocity v along the axis of a current - carrying solenoid, then :

A horizontal wire, of length $5 \mathrm{~cm}$ and carrying a current of $2\mathrm{A}$ placed in the middle of a long solenoid and right angles to its axis. The solenoid has 1000 turns per metre and carries a steady current I. Calculate I if the force on the wire is vertically downwards and equal to $10^{-4} \mathrm{~N}$.

A circuit to verify Ohm’s law uses ammeter and voltmeter in series or parallel connected correctly to the resistor. In the circuit

The relation between voltage sensitivity $({\sigma _V})$ and current sensitivity $\left( {{\sigma _i}} \right)$ of a moving coil galvanometer is (resistance of galvanometer is G).

A circular loop of radius 0.0157 m carries a current of 2 Amperes. The magnetic field at the centre of the loop is $\left[ {{\mu _ \circ } = 4\pi \times {{10}^{ - 7}}\,\,wb/A - m} \right]\,\left[ {in\,\,wb/{m^2}} \right]$

A long solenoid with 2000 turns per meter has a small loop of radius $3 \mathrm{~cm}$ placed inside the solenoid normal to its axis. If the current through the solenoid increases steadily from 1.5 A to $5.5 \mathrm{~A}$ in $\frac{\pi^2}{100} \mathrm{~s}$, the induced emf in the loop is

A particle of mass $m$ and charge $q$ enters a magnetic field $B$ perpendicularly with a velocity $v$, the radius of the circular path described by it will be

A charged particle of unit mass and unit charge moves with velocity of $\vec{v}=(8 \hat{i}+6 \hat{j}) \mathrm{m} / \mathrm{s}$ in a magnetic field of $\vec{B}=2 \hat{k} T.$
Then choose wrong statement.

Statement-A: When a charge particle of charge '$q$' moves with a velocity $v$ in magnetic field of induction $\vec{B}$ then force acting on it $\vec{F}=q(\vec{V} \times \vec{B})$

Statement-B: An electron is projected in a magnetic field along the lines of force then their will be no effect on the motion of electron.

The following statement is false for Helmholtz coils:

A wire $28 \mathrm{~m}$ long is bent into $N$ turns of circular coil of diameter $14 \mathrm{~cm}$ forming a solenoid of length $60 \mathrm{~cm}$. Calculate the flux density inside it when a current of $5\,\mathrm{amp}$ passed through it. $\left(\mu_0=12.57 \times 10^{-7} \mathrm{~m}^{-1}\right)$

An electron of mass $9 \times 10^{-31} \mathrm{~kg}$ and charge 1.6 $\times 10^{-19} \mathrm{C}$ moving with a velocity of $10^6 \mathrm{~ms}^{-1}$ entered a magnetic field normally and described a circle of radius $10 \mathrm{~cm}$. Then the intensity of the magnetic field is

When a proton has a velocity $\vec{v}=(2 \hat{i}+3 \hat{j}) \times 10^6 \mathrm{~ms}^{-1}$, it experiences a force $\vec{F}=-\left(1.28 \times 10^{-13} \hat{k}\right) \mathrm{N}$. When its velocity is along the $z$-axis, it experiences a force along the $x$-axis. What is the magnetic field?

An insulating rod of length $l$ carries a charge $q$ distributed uniformly on it. The rod is pivoted at an end and is rotated at a frequency $f$ about a fixed perpendicular axis. The magnetic moment of the system is :

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.

A current of $4 \mathrm{~A}$ produces a deflection of $30^{\circ}$ in the galvanometer. The figure of merit is

A magnetic field can be produced by :-

A proton carrying 1 MeV kinetic energy is moving
in a circular path of radius $R$ in uniform magnetic
field. What should be the energy of an a-particle
to describe a circle of the same radius in the same
field?

Assertion: Electron moving perpendicular to $\mathop B\limits^I$ will perform circular motion
Reason: Force by magnetic field is perpendicular to velocity

Assertion (A) : A charged particle moves along positive $y$-axis with constant velocity in uniform electric and magnetic fields. If magnetic field is acting along positive $x$-axis, then electric field should act along positive $z$-axis.

Reason (R) : To keep the charged particle undeviated the relation $\mathbf{E}=\mathbf{B} \times \mathbf{v}$ must hold good.

In a moving coil galvanometer, we use a radial magnetic feild so that the galvanometer scale is

To which of the following quantities, the radius
of the circular path of a charged particle
moving at right angles to a uniform magnetic
field is directly proportional?

Two galvanometers ' $G_1$ ' and ' $G_2$ ' require $2 \mathrm{~mA}$ and $3 \mathrm{~mA}$ respectively to produce the same deflection. Then

A charged particle moves through a magnetic field perpendicular to its direction, then

A magnetic dipole is placed under the effect of two magnetic fields inclined at $75^{\circ}$ to each other. One of the field has a magnetic induction of $1.5 \times 10^{-2} \mathrm{~T}$. The magnet comes to rest at an angle of $30^{\circ}$ with the direction of this field. The magnitude of the other field 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

Identify the correct statement from the following

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

Cyclotron is a device which is used to: