Magnetic effect of current practice · Mixed difficulty

A circular loop of radius 0.0157 m carries a current of 2.0 A. The magnetic field at the center of the loop is

$\left[ {{\mathrm{\mu }_0} = 4\pi \times {{10}^{ - 7}}\mathrm{Wb} - {\mathrm{A}^{ - 1}}{\mathrm{m}^{ - 1}}} \right]$

Statement I: An electron moving in the positive $x$-direction enters a region where uniform electric and magnetic fields exist perpendicular to each other. The electric field is in the negative $y$-direction. If the electron travels undeflected in this region, the direction of the magnetic field is along the negative $z$-axis.

Statement II: If a charged particle moves in a direction perpendicular to a magnetic field, the direction of the force acting on it is given by Fleming's left hand rule.

A straight wire of length of $\mathrm{0}.\mathrm{5}\,\,\mathrm{metre}$ and carrying a current of $1.2\,\,ampere$ is placed in a uniform magnetic field of induction 2 tesla. If the magnetic field is perpendicular to the length of the wire, the force acting on the wire is

A galvanometer gives full scale deflection with $0.2 \mathrm{~A}$ in its coil. The resistance of its coil is $10\, \Omega$. How much shunt resistance is required to convert it into an ammeter to read current upto $1.8 \mathrm{~A}$ ?

A direct current flows through a solenoid, entering in an anticlockwise sense at the end A. This solenoid, made to float on still water will:

A particle moving in the $xy$-plane experiences a velocity dependent force $F = k\left( {{v_y}\hat i + {v_x}\hat j} \right),$ where ${v_x}\mathrm{ }$ and ${v_y}$ are the $x$ and $y$ components of its velocity $v.$ If $a$ is the acceleration of the particle, then which of the following statements is true for the particle?

A wire of length L is placed parallel to the lines
of force in a uniform magnetic field B. If I is
the current in the wire, then it will experience:

The magnetic dipole moment of a current carrying conducting loop depends on

A solenoid of length 0.4 m and having 500 turns of wire carries a current of 3 amp. A thin coil having 10 turns of wire and of radius 0.01 m carries a current of 0.4 amp. Calculate the torque required to hold the coil in the middle of the solenoid with its axis perpendicular to the axis of solenoid

Charge $q$ is uniformly spread on a thin ring of radius $R$. The ring rotates about its axis with a uniform frequency $f$ Hz. The magnitude of magnetic induction at the centre of the ring is

The cyclotron assembly is filled with

Field inside a solenoid is

A straight wire carrying current $i$ is turned into a circular loop. If the magnitude of magnetic moment associated with it in M.K.S. unit is $M$, the length of wire will be

A charged particle is moving in the presence of electric field ${\mathbf{\vec E}}$ and magnetic field $\mathbf{\vec B}.$ The directions of $\mathbf{\vec E}\;$ and ${\mathbf{\vec B}}$ are such that the charged particle moves in a straight line and its speed increases. The relations amongst ${\mathbf{\vec E}}$ , ${\mathbf{\vec B}}$ and velocity ${\mathbf{\vec v}}$ must be such that

A charged particle with charge $q$ enters a region of constant, uniform and mutually orthogonal fields $\mathbf{E}$ and $\mathbf{B}$ with a velocity $\mathbf{v}$ perpendicular to both $\mathbf{E}\;and\;\mathbf{B}$, and comes out without any change in magnitude or direction of $\mathbf{v}$. Then

A tightly wound long solenoid carries a current of 1.5 A. An electron is executing uniform circular motion inside the solenoid with a time period of 75 ns. The number of turns per metre in the solenoid is ____.

[Take mass of electron $m_e=9 \times 10^{-31} \mathrm{~kg},$ charge of electron $\left|{q}_{{e}}\right|=1.6 \times 10^{-19} \mathrm{C},$ $\mu_0=4 \pi \times 10^{-7} \frac{\mathrm{N}}{\mathrm{A}^2},$ $\left.1 \mathrm{~ns}=10^{-9} \mathrm{~s}\right]$

The ratio of voltage sensitivity (${V_S}$) and current sensitivity (${I_s}$) of a moving coil galvanometer is

A current carrying small loop behaves like a small magnet. If $A$ be its area and $M$ its magnetic moment, the current in the loop will be

The coils $A$ and $B$ having the radii in the ratio $1:2$ carrying currents in the ratio 5:1 and have the number of turns in the ratio 1:5. The ratio of magnetic inductions at their centres is

The magnetic field at the center of current I carrying loop of radius $r$, is

Consider a wire carrying a steady current, $i$ placed in a uniform magnetic field ${B}$ perpendicular to its length. Consider the charges inside the wire. It is known that magnetic forces do no work. This implies that,

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

A circular current carrying coil has a radius R. The distance from the centre of the coil on the axis where the magnetic induction will be ${\left( {1/8} \right)^{\mathrm{th}}}$ of its value at the centre of the coil, is

A current carrying conductor placed in a magnetic field experiences maximum force when angle between current and magnetic field is

Tangent galvanometer measures

The ratio of time periods of $\alpha$-particle and proton moving on circular path in uniform transverse magnetic field :-

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 :

In a solenoid, if number of turns is doubled. then self inductance will become

The magnetic field $B$ at a point on one end of a solenoid having $n$ turns per metre length and carrying a current of $i$ ampere is given by

Magnetic field dB to a current element at any
point on its axis is