JEE Main
Physics
Magnetics
Previous Years Questions

A coil is placed in magnetic field such that plane of coil is perpendicular to the direction of magnetic field. The magnetic flux through a coil can b...
As shown in the figure, a long straight conductor with semicircular arc of radius $$\frac{\pi}{10}$$m is carrying current $$\mathrm{I=3A}$$. The magni...
Find the magnetic field at the point $$\mathrm{P}$$ in figure. The curved portion is a semicircle connected to two long straight wires. ...
A long conducting wire having a current I flowing through it, is bent into a circular coil of $\mathrm{N}$ turns. Then it is bent into a circular coil...
A bar magnet with a magnetic moment $$5.0 \mathrm{Am}^{2}$$ is placed in parallel position relative to a magnetic field of $$0.4 \mathrm{~T}$$. The am...
A rod with circular cross-section area $$2 \mathrm{~cm}^{2}$$ and length $$40 \mathrm{~cm}$$ is wound uniformly with 400 turns of an insulated wire. I...
As shown in the figure, a current of $2 \mathrm{~A}$ flowing in an equilateral triangle of side $4 \sqrt{3} \mathrm{~cm}$. The magnetic field at the c...
A current carrying rectangular loop PQRS is made of uniform wire. The length $P R=Q S=5 \mathrm{~cm}$ and $P Q=R S=100 \mathrm{~cm}$. If ammeter curre...
A massless square loop, of wire of resistance $$10 \Omega$$, supporting a mass of $$1 \mathrm{~g}$$, hangs vertically with one of its sides in a unifo...
The magnetic moments associated with two closely wound circular coils $$\mathrm{A}$$ and $$\mathrm{B}$$ of radius $$\mathrm{r}_{\mathrm{A}}=10$$ $$\ma... A square loop of area 25 cm$$^2$$has a resistance of 10$$\Omega$$. The loop is placed in uniform magnetic field of magnitude 40.0 T. The plane of lo... The electric current in a circular coil of four turns produces a magnetic induction 32 T at its centre. The coil is unwound and is rewound into a circ... The magnitude of magnetic induction at mid point$$\mathrm{O}$$due to current arrangement as shown in Fig will be ... A single current carrying loop of wire carrying current I flowing in anticlockwise direction seen from +ve$$\mathrm{z}$$direction and lying in$$x y...
For a moving coil galvanometer, the deflection in the coil is 0.05 rad when a current of 10 mA is passes through it. If the torsional constant of susp...
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A solenoid of 1200 turns is wound uniformly in a single layer on a glass tube 2 m long and 0.2 m in diameter. The magnetic intensity at the center of ...
A long solenoid is formed by winding 70 turns cm$$^{-1}$$. If 2.0 A current flows, then the magnetic field produced inside the solenoid is ___________...
Two long straight wires P and Q carrying equal current 10A each were kept parallel to each other at 5 cm distance. Magnitude of magnetic force experie...
A circular loop of radius $$r$$ is carrying current I A. The ratio of magnetic field at the center of circular loop and at a distance r from the cente...
A wire X of length $$50 \mathrm{~cm}$$ carrying a current of $$2 \mathrm{~A}$$ is placed parallel to a long wire $$\mathrm{Y}$$ of length $$5 \mathrm{... The vertical component of the earth's magnetic field is$$6 \times 10^{-5} \mathrm{~T}$$at any place where the angle of dip is$$37^{\circ}$$. The ea... A triangular shaped wire carrying$$10 \mathrm{~A}$$current is placed in a uniform magnetic field of$$0.5 \mathrm{~T}$$, as shown in figure. The mag... The magnetic field at the center of current carrying circular loop is$$B_{1}$$. The magnetic field at a distance of$$\sqrt{3}$$times radius of the ... The current sensitivity of a galvanometer can be increased by : (A) decreasing the number of turns (B) increasing the magnetic field (C) decreasing th... As shown in the figure, a metallic rod of linear density$$0.45 \mathrm{~kg} \mathrm{~m}^{-1}$$is lying horizontally on a smooth inclined plane which... A compass needle of oscillation magnetometer oscillates 20 times per minute at a place$$\mathrm{P}$$of$$\operatorname{dip} 30^{\circ}$$. The number... A cyclotron is used to accelerate protons. If the operating magnetic field is$$1.0 \mathrm{~T}$$and the radius of the cyclotron 'dees' is$$60 \math...
Identify the correct statements from the following descriptions of various properties of electromagnetic waves. (A) In a plane electromagnetic wave el...
Two bar magnets oscillate in a horizontal plane in earth's magnetic field with time periods of $$3 \mathrm{~s}$$ and $$4 \mathrm{~s}$$ respectively. I...
A magnet hung at $$45^{\circ}$$ with magnetic meridian makes an angle of $$60^{\circ}$$ with the horizontal. The actual value of the angle of dip is -...
A beam of light travelling along $$X$$-axis is described by the electric field $$E_{y}=900 \sin \omega(\mathrm{t}-x / c)$$. The ratio of electric forc...
Two concentric circular loops of radii $$r_{1}=30 \mathrm{~cm}$$ and $$r_{2}=50 \mathrm{~cm}$$ are placed in $$\mathrm{X}-\mathrm{Y}$$ plane as shown ...
A velocity selector consists of electric field $$\vec{E}=E \,\hat{k}$$ and magnetic field $$\vec{B}=B \,\hat{j}$$ with $$B=12 \,m T$$. The value of $$... A charge particle is moving in a uniform magnetic field$$(2 \hat{i}+3 \hat{j}) \,\mathrm{T}$$. If it has an acceleration of$$(\alpha \hat{i}-4 \hat{...
$$\mathrm{B}_{X}$$ and $$\mathrm{B}_{\mathrm{Y}}$$ are the magnetic fields at the centre of two coils $$\mathrm{X}$$ and $$\mathrm{Y}$$ respectively e...
An electron with energy 0.1 keV moves at right angle to the earth's magnetic field of 1 $$\times$$ 10$$-$$4 Wbm$$-$$2. The frequency of revolution of ...
Two charged particles, having same kinetic energy, are allowed to pass through a uniform magnetic field perpendicular to the direction of motion. If t...
The magnetic moment of an electron (e) revolving in an orbit around nucleus with an orbital angular momentum is given by :
A coil of n number of turns wound tightly in the form of a spiral with inner and outer radii r1 and r2 respectively. When a current of strength I is p...
Two long current carrying conductors are placed to each other at a distance of 8 cm between them. The magnitude of magnetic field produced at mid-poin...
Given below are two statements : Statement I : The electric force changes the speed of the charged particle and hence changes its kinetic energy; wher...
A charge particle moves along circular path in a uniform magnetic field in a cyclotron. The kinetic energy of the charge particle increases to 4 times...
At a certain place the angle of dip is 30$$^\circ$$ and the horizontal component of earth's magnetic field is 0.5 G. The earth's total magnetic field ...
The space inside a straight current carrying solenoid is filled with a magnetic material having magnetic susceptibility equal to 1.2 $$\times$$ 10$$-... Two parallel, long wires are kept 0.20 m apart in vacuum, each carrying current of x A in the same direction. If the force of attraction per meter of ... A coil is placed in a time varying magnetic field. If the number of turns in the coil were to be halved and the radius of wire doubled, the electrical... An infinitely long hollow conducting cylinder with radius R carries a uniform current along its surface. Choose the correct representation of magnetic... A radar sends an electromagnetic signal of electric field (E0) = 2.25 V/m and magnetic field (B0) = 1.5$$\times$$10$$-$$8 T which strikes a target o... The susceptibility of a paramagnetic material is 99. The permeability of the material in Wb/A-m, is : [Permeability of free space$$\mu$$0 = 4$$\pi$$... A bar magnet having a magnetic moment of 2.0$$\times$$105 JT$$-$$1, is placed along the direction of uniform magnetic field of magnitude B = 14$$...
A metallic conductor of length 1 m rotates in a vertical plane parallel to east-west direction about one of its end with angular velocity 5 rad s$$-$$...
A metal surface is illuminated by a radiation of wavelength 4500 $$\mathop A\limits^o$$. The ejected photo-electron enters a constant magnetic field ...
A proton and an alpha particle of the same velocity enter in a uniform magnetic field which is acting perpendicular to their direction of motion. The ...
Given below are two statements : Statement I : Susceptibilities of paramagnetic and ferromagnetic substances increase with decrease in temperature. St...
A long solenoid carrying a current produces a magnetic field B along its axis. If the current is doubled and the number of turns per cm is halved, the...
A long straight wire with a circular cross-section having radius R, is carrying a steady current I. The current I is uniformly distributed across this...
The soft-iron is a suitable material for making an electromagnet. This is because soft-iron has
A proton, a deutron and an $$\alpha$$-particle with same kinetic energy enter into a uniform magnetic field at right angle to magnetic field. The rati...
An electric bulb is rated as 200 W. What will be the peak magnetic field at 4 m distance produced by the radiations coming from this bulb? Consider th...
Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : In an uniform magnetic fiel...
The magnetic field at the centre of a circular coil of radius r, due to current I flowing through it, is B. The magnetic field at a point along the ax...
A square loop of side 20 cm and resistance 1$$\Omega$$ is moved towards right with a constant speed v0. The right arm of the loop is in a uniform magn...
Following plots show magnetization (M) vs magnetizing field (H) and magnetic susceptibility ($$\chi$$) vs temperature (T) graph :Which of the followi...
Electric field of plane electromagnetic wave propagating through a non-magnetic medium is given by E = 20cos(2 $$\times$$ 1010 t $$-$$ 200x) V/m. The ...
There are two infinitely long straight current carrying conductors and they are held at right angles to each other so that their common ends meet at t...
A current of 1.5 A is flowing through a triangle, of side 9 cm each. The magnetic field at the centroid of the triangle is :(Assume that the current i...
The magnetic field vector of an electromagnetic wave is given by $$B = {B_0}{{\widehat i + \widehat j} \over {\sqrt 2 }}\cos (kz - \omega t)$$; where ...
A coil is placed in a magnetic field $$\overrightarrow B$$ as shown below :A current is induced in the coil because $$\overrightarrow B$$ is :...
A coil having N turns is wound tightly in the form of a spiral with inner and outer radii 'a' and 'b' respectively. Find the magnetic field at centre,...
A constant magnetic field of 1T is applied in the x > 0 region. A metallic circular ring of radius 1m is moving with a constant velocity of 1 m/s a...
A coaxial cable consists of an inner wire of radius 'a' surrounded by an outer shell of inner and outer radii 'b' and 'c' respectively. The inner wire...
A bar magnet is passing through a conducting loop of radius R with velocity $$\upsilon$$. The radius of the bar magnet is such that it just passes th...
Two ions of masses 4 amu and 16 amu have charges +2e and +3e respectively. These ions pass through the region of constant perpendicular magnetic field...
A light beam is described by $$E = 800\sin \omega \left( {t - {x \over c}} \right)$$. An electron is allowed to move normal to the propagation of ligh...
The fractional change in the magnetic field intensity at a distance 'r' from centre on the axis of current carrying coil of radius 'a' to the magnetic...
Figure A and B shown to long straight wires of circular cross-section (a and b with a < b), carrying current I which is uniformly distributed acros...
Two ions having same mass have charges in the ratio 1 : 2. They are projected normally in a uniform magnetic field with their speeds in the ratio 2 : ...
A linearly polarized electromagnetic wave in vacuum is $$E = 3.1\cos \left[ {(1.8)z - (5.4 \times {{10}^6})t} \right]\widehat iN/C$$is incident normal...
Choose the correct option
Intensity of sunlight is observed as 0.092 Wm$$-$$2 at a point in free space. What will be the peak value of magnetic field at the point?($${\varepsil... Statement I : The ferromagnetic property depends on temperature. At high temperature, ferromagnet becomes paramagnet.Statement II : At high temperatur... In an electromagnetic wave the electric field vector and magnetic field vector are given as$$\overrightarrow E = {E_0}\widehat i$$and$$\overrighta...
At an angle of 30$$^\circ$$ to the magnetic meridian, the apparent dip is 45$$^\circ$$. Find the true dip :
The magnetic susceptibility of a material of a rod is 499. Permeability in vacuum is 4$$\pi$$ $$\times$$ 10$$-$$7 H/m. Absolute permeability of the ma...
A deuteron and an alpha particle having equal kinetic energy enter perpendicularly into a magnetic field. Let rd and r$$\alpha$$ be their respective r...
The arm PQ of a rectangular conductor is moving from x = 0 to x = 2b outwards and then inwards from x = 2b to x = 0 as shown in the figure. A uniform ...
A plane electromagnetic wave propagating along y-direction can have the following pair of electric field $$\left( {\overrightarrow E } \right)$$ and m...
Which of the following statements are correct?(A) Electric monopoles do not exist whereas magnetic monopoles exist.(B) Magnetic field lines due to a s...
A plane electromagnetic wave of frequency 100 MHz is travelling in vacuum along the x-direction. At a particular point in space and time, $$\overright... Four identical long solenoids A, B, C and D are connected to each other as shown in the figure. If the magnetic field at the center of A is 3T, the fi... A loop of flexible wire of irregular shape carrying current is placed in an external magnetic field. Identify the effect of the field on the wire. A hairpin like shape as shown in figure is made by bending a long current carrying wire. What is the magnitude of a magnetic field at point P which li... A solenoid of 1000 turns per metre has a core with relative permeability 500. Insulated windings of the solenoid carry an electric current of 5A. The ... A charge Q is moving$$\overrightarrow {dl} $$distance in the magnetic field$$\overrightarrow {B} $$. Find the value of work done by$$\overrightarr...
The magnetic field in a region is given by $$\overrightarrow B = {B_o}\left( {{x \over a}} \right)\widehat k$$. A square loop of side d is placed wit...
A plane electromagnetic wave of frequency 500 MHz is travelling in vacuum along y-direction. At a particular point in space and time, $$\overrightarro... A bar manet of length 14 cm is placed in the magnetic meridian with its north pole pointing towards the geographic north pole. A neutral point is obta... For an electromagnetic wave travelling in free space, the relation between average energy densities due to electric (Ue) and magnetic (Um) fields is :... A conducting bar of length L is free to slide on two parallel conducting rails as shown in the figure Two resistors R1 and R2 are connected across the... An aeroplane, with its wings spread 10 m, is flying at a speed of 180 km/h in a horizontal direction. The total intensity of earth's field at that par... In a ferromagnetic material, below the curie temperature, a domain is defined as : A proton, a deuteron and an$$\alpha$$particle are moving with same momentum in a uniform magnetic field. The ratio of magnetic forces acting on them... Magnetic fields at two points on the axis of a circular coil at a distance of 0.05 m and 0.2 m from the centre are in the ratio 8 : 1. The radius of c... A soft ferromagnetic material is placed in an external magnetic field. The magnetic domains : For a plane electromagnetic wave, the magnetic field at a point x and time t is$$\overrightarrow B \left( {x,t} \right)$$=$$\left[ {1.2 \times {{10...
A charged particle going around in a circle can be considered to be a current loop. A particle of mass m carrying charge q is moving in a plane with s...
A square loop of side 2$$a$$ and carrying current I is kept in xz plane with its centre at origin. A long wire carrying the same current I is placed p...
An electron is moving along +x direction with a velocity of 6 $$\times$$ 106 ms–1. It enters a region of uniform electric field of 300 V/cm pointin...
A particle of charge q and mass m is moving with a velocity $$- v\widehat i$$ (v $$\ne$$ 0) towards a large screen placed in the Y - Z plane at a d...
The quantities x = $${1 \over {\sqrt {{\mu _0}{\varepsilon _0}} }}$$, y = $${E \over B}$$ and z = $${l \over {CR}}$$ are defined where C-capacitance, ...
An iron rod of volume 10–3 m3 and relative permeability 1000 is placed as core in a solenoid with 10 turns/cm. If a current of 0.5 A is passed through...
A galvanometer is used in laboratory for detecting the null point in electrical experiments. If, on passing a current of 6 mA it produces a deflection...
An infinitely long, straight wire carrying current I, one side opened rectangular loop and a conductor C with a sliding connector are located in the s...
An electron is constrained to move along the y-axis with a speed of 0.1 c (c is the speed of light) in the presence of electromagnetic wave, whose ele...
A square loop of side 2$$a$$, and carrying current I, is kept in XZ plane with its centre at origin. A long wire carrying the same current I is placed...
A circular coil has moment of inertia 0.8 kg m2 around any diameter and is carrying current to produce a magnetic moment of 20 Am2 . The coil is kept...
The electric field of a plane electromagnetic wave is given by $$\overrightarrow E = {E_0}\left( {\widehat x + \widehat y} \right)\sin \left( {kz - \... A paramagnetic sample shows a net magnetisation of 6 A/m when it is placed in an external magnetic field of 0.4 T at a temperature of 4 K. When the sa... A small bar magnet placed with its axis at 30o with an external field of 0.06 T experiences a torque of 0.018 Nm. The minimum work required to rotate ... A wire A, bent in the shape of an arc of a circle, carrying a current of 2 A and having radius 2 cm and another wire B, also bent in the shape of arc ... A small bar magnet is moved through a coil at constant speed from one end to the other. Which of the following series of observations will be seen on ... A uniform magnetic field B exists in a direction perpendicular to the plane of a square loop made of a metal wire. The wire has a diameter of 4 mm and... A perfectly diamagnetic sphere has a small spherical cavity at its centre, which is filled with a paramagnetic substance. The whole system is placed i... A charged particle carrying charge 1$$\mu $$C is moving with velocity$$\left( {2\widehat i + 3\widehat j + 4\widehat k} \right)$$ms–1. If an extern... An elliptical loop having resistance R, of semi major axis a, and semi minor axis b is placed in magnetic field as shown in the figure. If the loop is... Magnitude of magnetic field (in SI units) at the centre of a hexagonal shape coil of side 10 cm, 50 turns and carrying current I (Ampere) in units of ... The figure shows a region of length ‘l’ with a uniform magnetic field of 0.3 T in it and a proton entering the region with velocity 4$$ \times $$105... A wire carrying current I is bent in the shape ABCDEFA as shown, where rectangle ABCDA and ADEFA are perpendicular to each other. If the sides of the ... Magnetic materials used for making permanent magnets (P) and magnets in a transformer (T) have different properties of the following, which property b... A beam of protons with speed 4 × 105 ms–1 enters a uniform magnetic field of 0.3 T at an angle of 60° to the magnetic field. The pitch of the resultin... An electron gun is placed inside a long solenoid of radius R on its axis. The solenoid has n turns/length and carries a current I. The electron gun sh... A plane electromagnetic wave is propagating along the direction$${{\widehat i + \widehat j} \over {\sqrt 2 }}$$, with its polarization along the dir... A small circular loop of conducting wire has radius a and carries current I. It is placed in a uniform magnetic field B perpendicular to its plane suc... A long, straight wire of radius a carries a current distributed uniformly over its cross-section. The ratio of the magnetic fields due to the wire at ... The electric fields of two plane electromagnetic plane waves in vacuum are given by$$\overrightarrow {{E_1}} = {E_0}\widehat j\cos \left( {\omega t ...
A charged particle of mass 'm' and charge 'q' moving under the influence of uniform electric field $$E\overrightarrow i$$ and a uniform magnetic fiel...
A plane electromagnetic wave of frequency 25 GHz is propagating in vacuum along the z-direction. At a particular point in space and time, the magnetic...
A very long wire ABDMNDC is shown in figure carrying current I. AB and BC parts are straight, long and at right angle. At D wire forms a circular turn...
Photon with kinetic energy of 1MeV moves from south to north. It gets an acceleration of 1012 m/s2 by an applied magnetic field (west to east). The va...
At time t = 0 magnetic field of 1000 Gauss is passing perpendicularly through the area defined by the closed loop shown in the figure. If the magnetic...
A particle of mass m and charge q has an initial velocity $$\overrightarrow v = {v_0}\widehat j$$ . If an electric field $$\overrightarrow E = {E_0}... The figure gives experimentally measured B vs H variation in a ferromagnetic material. The retentivity, coercivity and saturation, respectively, of t... A planar loop of wire rotates in a uniform magnetic field. Initially at t = 0, the plane of the loop is perpendicular to the magnetic field. If it rot... The electric field of a plane electromagnetic wave is given by$$\overrightarrow E = {E_0}{{\widehat i + \widehat j} \over {\sqrt 2 }}\cos \left( {kz...
If the magnetic field in a plane electromagnetic wave is given by $$\overrightarrow B$$ = 3 $$\times$$ 10-8 sin(1.6 $$\times$$ 103x + 48 $$\time... An electron, moving along the x-axis with an initial energy of 100 eV, enters a region of magnetic field$$\overrightarrow B = \left( {1.5 \times {{1...
Find the magnetic field at point P due to a straight line segment AB of length 6 cm carrying a current of 5A. (See figure) ($$\mu$$0 = 4$$\pi$$ × 10...
A thin ring of 10 cm radius carries a uniformly distributed charge. The ring rotates at a constant angular speed of 40 $$\pi$$ rad s–1 about its axi...
The figure shows a square loop L of side 5 cm which is connected to a network of resistances. The whole setup is moving towards right with a constant ...
An electromagnetic wave is represented by the electric field $$\overrightarrow E = {E_0}\widehat n\sin \left[ {\omega t + \left( {6y - 8z} \right)} \... A magnetic compass needle oscillates 30 times per minute at a place where the dip is 45o, and 40 times per minute where the dip is 30o. If B1 and B2 a... A square loop is carrying a steady current I and the magnitude of its magnetic dipole moment is m. if this square loop is changed to a circular loop a... The magnitude of the magnetic field at the centre of an equilateral triangular loop of side 1 m which is carrying a current of 10 A is : [Take$$\mu $... A proton, an electron, and a Helium nucleus, have the same energy. They are in circular orbits in a plane due to magnetic field perpendicualr to the p... Two coils 'P' and 'Q' are separated by some distance. When a current of 3 A flows through coil 'P', a magnetic flux of 10–3 Wb passes through 'Q'. No ... A moving coil galvanometer has a coil with 175 turns and area 1 cm2. It uses a torsion band of torsion constant 10–6 N-m/rad. The coil is placed in a ... A rigid square loop of side 'a' and carrying current I2 is lying on a horizontal surface near a long current I1 carrying wire in the same plane as sho... The magnetic field of a plane electromagnetic wave is given by : $$\overline B = {B_0}\widehat i\left[ {\cos (kz - \omega t)} \right] + {B_i}\wideha... A rectangular coil (Dimension 5 cm × 2.5 cm) with 100 turns, carrying a current of 3 A in the clock-wise direction is kept centered at the origin and ... Two very long, straight, and insulated wires are kept at 90° angle from each other in xy-plane as shown in the figure. These wires carry currents of e... The magnetic field of an electromagnetic wave is given by :-$$\mathop B\limits^ \to = 1.6 \times {10^{ - 6}}\cos \left( {2 \times {{10}^7}z + 6 \ti... Two magnetic dipoles X and Y are placed at a separation d, with their axes perpendicular to each other. The dipole moment of Y is twice that of X. A p... A circular coil having N turns and radius r carries a current I. It is held in the XZ plane in a magnetic field B$${\mathop i\limits^ \wedge }$$ . Th... A thin strip 10 cm long is on a U shaped wire of negligible resistance and it is connected to a spring of spring constant 0.5 Nm–1 (see figure). The a... A plane electromagnetic wave travels in free space along the x-direction. The electric field component of the wave at a particular point of space and ... The mean intensity of radiation on the surface of the Sun is about 108 W/m2 . The rms value of the corresponding magnetic field is closet to :... As shown in the figure, two infinitely long, identical wires are bent by 90o and placed in such a way that the segments LP and QM are along the x-axis... A proton and an $$\alpha$$-particle (with their masses in the ratio of 1 : 4 and charges in the ratio of 1 : 2) are accelerated from rest through a p... The region between y = 0 and y = d contains a magnetic field $$\overrightarrow B = B\widehat z$$. A particle of mass m and charge q enters the regio... A particle of mass m and charge q is in an electric and magnetic field given by $$\overrightarrow E = 2\widehat i + 3\widehat j;\,\,\,\overrightarrow... In an experiment, electrons are accelerated, from rest, by applying a voltage of 500 V. Calculate the radius of the path if a magnetic field 100 mT is... There are two long co-axial solenoids of same length$$l$$. The inner and outer coils have radii r1 and r2 and number of turns per unit length n1 and ... At some location on earth the horizontal component of earth’s magnetic field is 18 × 10–6 T. At this location, magnetic needle of length 0.12 m and po... A hoop and a solid cylinder of same mass and radius are made of a permanent magnetic material with their magnetic moment parallel to their respective ... A magnet of total magnetic moment 10-2$${\widehat i}$$A-m2 is placed in a time varying magnetic field, B$${\widehat i}$$(co where B = 1 Tesla and$$... A solid metal cube of edge length 2 cm is moving in a positive y-direction at a constant speed of 6 m/s. There is a uniform magnetic field of 0.1 T in... An insulating thin rod of length $$l$$ has a linear charge density $$\rho \left( x \right)$$ = $${\rho _0}{x \over l}$$ on it. The rod is rotated abou... The energy associated with electric field is (UE) and with magnetic field is (UB) for an electromagnetic wave in free space. Then : ... A particle having the same charge as of electron moves in a ciurcular path of radius 0.5 cm under the influence of a magnetic field 0f 0.5 T. If an el... One of the two identical conducting wires of length L is bent in the form of a circular loop and the other one into a circular coil of N identical tur... A current loop, having two circular arcs joined by two radial lines is shown in the figure. It carries a current of 10 A. The magnetic field at point ... A conducting circular loop made of a thin wire, has area 3.5 $$\times$$ 10$$-$$3 m2 and resistance 10 $$\Omega$$. It is placed perpendicular to a t... An infinitely long current carrying wire and a small current carrying loop are in the plane of the paper as shown. The radius of the loop is a and dis... A plane electromagnetic wave of frequency 50 MHz travels in free space along the positive x-direction. At a particular point in space and time, $$\ov... A bar magnet is demagnetized by inserting it inside a solenoid of length 0.2 m, 100 turns, and carrying a current of 5.2 m, 100 turns, and carrying a ... A galvanometer with its coil resistance 25$$\Omega $$requires a current of 1 mA for its full deflection. In order to construct an ammeter to read up... A charge q is spread uniformly over an insulated loop of radius r. If it is rotated with an angular velocity$$\omega $$with resect to normal axis t... An electron, a proton and an alpha particle having the same kinetic energy are moving in circular orbits of radii re, rp, r$$_\alpha$$respectively in... The dipole moment of a circular loop carrying a current I, is m and the magnetic field at the centre of the loop is B1. When the dipole moment is doub... A current of 1 A is flowing on the sides of an equilateral triangle of side 4.5$$ \times $$10-2 m. The magnetic field at the center of the triangle ... A Helmholtz coil has a pair of loops, each with$$N$$turns and radius$$R$$. They are placed coaxially at distance$$R$$and the same current$${\rm ... The $$B$$-$$H$$ curve for a ferromagnet is shown in the figure. The ferromagnet is placed inside a long solended with $$1000$$ turns/cm. The current t... A negative test charge is moving near a long straight wire carrying a current. The force acting on the test charge is parallel to the direction of the... A uniform magnetic field B of 0.3 T is along the positive Z-direction. A rectangular loop (abcd) of sides 10 cm × 5 cm carries a current I of 12 A. Ou... In a certain region static electric and magnetic fields exist. The magnetic field is given by $$\overrightarrow B = {B_0}\left( {\widehat i + 2\wideh... A magnetic dipole in a constant magnetic field has : Magnetic field in a plane electromagnetic wave is given by$$\overrightarrow B $$= B0 sin (k x +$$\omega $$t)$$\widehat j\,T$$Expression for corr... A magnetic needle of magnetic moment 6.7$$\times$$10-2 A m2 and moment of inertia 7.5$$\times$$10-6 kg m2 is performing simple harmonic oscillatio... When a current of 5 mA is passed through a galvanometer having a coil of resistance 15$$\Omega $$, it shows full scale deflection. The value of the re... A fighter plane of length 20 m, wing span (distance from tip of one wing to the tip of the other wing) of 15 m and height 5 m is flying towards east o... Consider a thin metallic sheet perpendicular to the plane of the paper moving with speed ‘v’ in a uniform magnetic field B going into the plane of the... A galvanometer has a 50 division scale. Battery has no internal resistance. It is found that there is deflection of 40 divisions when R = 2400$$\Omeg... A magnetic dipole is acted upon by two magnetic fields which are inclined to each other at an angle of 75o. One of the fields has a magnitude of 15 mT... A 50 $$\Omega$$ resistance is connected to a battery of 5 V. A galvanometer of resistance 100 $$\Omega$$ is to be used as an ammeter to measure curr... To know the resistance G of a galvanometer by half deflection method, a battery of emf VE and resistance R is used to deflect the galvanometer by angl... Two identical wires $$A$$ and $$B,$$ each of length $$'l'$$, carry the same current $$I$$. Wire $$A$$ is bent into a circle of radius $$R$$ and wire$...
A galvanometer having a coil resistance of $$100\,\Omega$$ gives a full scale deflection, when a currect of $$1$$ $$mA$$ is passed through it. The va...
Hysteresis loop for two magnetic materials $$A$$ and $$B$$ are given below : These materials are used to make magnets for electric generators, trans...
Two long current carrying thin wires, both with current $$I,$$ are held by insulating threads of length $$L$$ and are in equilibrium as shown in the f...
A rectangular loop of sides $$10$$ $$cm$$ and $$5$$ $$cm$$ carrying a current $$1$$ of $$12A$$ is placed in different orientations as shown in the fig...
The coercivity of a small magnet where the ferromagnet gets demagnetized is $$3 \times {10^3}\,A{m^{ - 1}}.$$ The current required to be passed in a s...
A conductor lies along the $$z$$-axis at $$- 1.5 \le z < 1.5\,m$$ and carries a fixed current of $$10.0$$ $$A$$ in $$- {\widehat a_z}$$ direction...
Two short bar magnets of length $$1$$ $$cm$$ each have magnetic moments $$1.20$$ $$A{m^2}$$ and $$1.00$$ $$A{m^2}$$ respectively. They are placed on ...
Proton, deuteron and alpha particle of same kinetic energy are moving in circular trajectories in a constant magnetic field. The radii of proton, denu...
A charge $$Q$$ is uniformly distributed over the surface of non-conducting disc of radius $$R.$$ The disc rotates about an axis perpendicular to its p...
A current $$I$$ flows in an infinitely long wire with cross section in the form of a semi-circular ring of radius $$R.$$ The magnitude of the magnetic...
Two long parallel wires are at a distance $$2d$$ apart. They carry steady equal currents flowing out of the plane of the paper as shown. The variation...
A current loop $$ABCD$$ is held fixed on the plane of the paper as shown in the figure. The arcs $$BC$$ (radius $$= b$$) and $$DA$$ (radius $$=a$$) of...
A current loop $$ABCD$$ is held fixed on the plane of the paper as shown in the figure. The arcs $$BC$$ (radius $$= b$$) and $$DA$$ (radius $$=a$$) of...
Relative permittivity and permeability of a material $${\varepsilon _r}$$ and $${\mu _r},$$ respectively. Which of the following values of these quant...
A horizontal overhead powerline is at height of $$4m$$ from the ground and carries a current of $$100A$$ from east to west. The magnetic field directl...
A charged particle with charge $$q$$ enters a region of constant, uniform and mutually orthogonal fields $$\overrightarrow E$$ and $$\overrightarrow ... A current$$I$$flows along the length of an infinitely long, straight, thin walled pipe. Then A long straight wire of radius$$a$$carries a steady current$$i.$$The current is uniformly distributed across its cross section. The ratio of the ... A charged particle moves through a magnetic field perpendicular to its direction. Then Two identical conducting wires$$AOB$$and$$COD$$are placed at right angles to each other. The wire$$AOB$$carries an electric current$${I_1}$$an... Needles$${N_1}$$,$${N_2}$$and$${N_3}$$are made of ferromagnetic, a paramagnetic and a diamagnetic substance respectively. A magnet when brought c... In a region, steady and uniform electric and magnetic fields are present. These two fields are parallel to each other. A charged particle is released ... A long solenoid has$$200$$turns per$$cm$$and carries a current$$i.$$The magnetic field at its center is$$6.28 \times {10^{ - 2}}\,\,\,Weber/{m^...
Two thin, long, parallel wires, separated by a distance $$'d'$$ carry a current of $$'i'$$ $$A$$ in the same direction. They will
Two concentric coils each of radius equal to $$2$$ $$\pi$$ $$cm$$ are placed at right angles to each other. $$3$$ ampere and $$4$$ ampere are the c...
A magnetic needle is kept in a non-uniform magnetic field. It experiences
A uniform electric field and a uniform magnetic field are acting along the same direction in a certain region. If an electron is projected along the d...
A charged particle of mass $$m$$ and charge $$q$$ travels on a circular path of radius $$r$$ that is perpendicular to a magnetic field $$B.$$ The time...
Curie temperature is the temperature above which
A current $$i$$ ampere flows along an infinitely long straight thin walled tube, then the magnetic induction at any point inside the tube is
A long wire carries a steady current. It is bent into a circle of one turn and the magnetic field at the centre of the coil is $$B.$$ It is then bent ...
The magnetic field due to a current carrying circular loop of radius $$3$$ $$cm$$ at a point on the axis at a distance of $$4$$ $$cm$$ from the centr...
The length of a magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is $$2s.$$ The magne...
Two long conductors, separated by a distance $$d$$ carry current $${I_1}$$ and $${I_2}$$ in the same direction. They exert a force $$F$$ on each other...
The materials suitable for making electromagnets should have
A thin rectangular magnet suspended freely has a period of oscillation equal to $$T.$$ Now it is broken into two equal halves (each having half of the...
A particle of mass $$M$$ and charge $$Q$$ moving with velocity $$\overrightarrow v$$ describe a circular path of radius $$R$$ when subjected to a uni...
A particle of charge $$- 16 \times {10^{ - 18}}$$ coulomb moving with velocity $$10m{s^{ - 1}}$$ along the $$x$$-axis enters a region where a magneti...
A magnetic needle lying parallel to a magnetic field requires $$W$$ units of work to turn it through $${60^ \circ }.$$ The torque needed to maintain t...
The magnetic lines of force inside a bar magnet
If in a circular coil $$A$$ of radius $$R,$$ current $$I$$ is flowing and in another coil $$B$$ of radius $$2R$$ a current $$2I$$ is flowing, then th...
If an electron and a proton having same momentum enter perpendicular to a magnetic field, then
The time period of a charged particle undergoing a circular motion in a uniform magnetic field is independent of its
Wires $$1$$ and $$2$$ carrying currents $$i{}_1$$ and $$i{}_2$$ respectively are inclined at an angle $$\theta$$ to each other. What is the force on ...

## Numerical

A charge particle of $$2 ~\mu \mathrm{C}$$ accelerated by a potential difference of $$100 \mathrm{~V}$$ enters a region of uniform magnetic field of m...
Two long parallel wires carrying currents 8A and 15A in opposite directions are placed at a distance of 7 cm from each other. A point P is at equidist...
A single turn current loop in the shape of a right angle triangle with sides 5 cm, 12 cm, 13 cm is carrying a current of 2 A. The loop is in a uniform...
A closely wounded circular coil of radius 5 cm produces a magnetic field of $$37.68 \times 10^{-4} \mathrm{~T}$$ at its center. The current through th...
A wire of length $$314 \mathrm{~cm}$$ carrying current of $$14 \mathrm{~A}$$ is bent to form a circle. The magnetic moment of the coil is ________ A $... A singly ionized magnesium atom (A = 24) ion is accelerated to kinetic energy 5 keV, and is projected perpendicularly into a magnetic field B of the m... A deuteron and a proton moving with equal kinetic energy enter into a uniform magnetic field at right angle to the field. If rd and rp are the radii o... A metallic rod of length 20 cm is placed in North-South direction and is moved at a constant speed of 20 m/s towards East. The horizontal component of... A circular coil of 1000 turns each with area 1m2 is rotated about its vertical diameter at the rate of one revolution per second in a uniform horizont... A long solenoid with 1000 turns/m has a core material with relative permeability 500 and volume 103 cm3. If the core material is replaced by another m... A plane electromagnetic wave with frequency of 30 MHz travels in free space. At particular point in space and time, electric field is 6 V/m. The magne... A uniform conducting wire of length is 24a, and resistance R is wound up as a current carrying coil in the shape of an equilateral triangle of side 'a... A circular coil of radius 8.0 cm and 20 turns is rotated about its vertical diameter with an angular speed of 50 rad s$$-$$1 in a uniform horizontal m... A coil in the shape of an equilateral triangle of side 10 cm lies in a vertical plane between the pole pieces of permanent magnet producing a horizont... The electric field in a plane electromagnetic wave is given by $$\overrightarrow E = 200\cos \left[ {\left( {{{0.5 \times {{10}^3}} \over m}} \right)... Two short magnetic dipoles m1 and m2 each having magnetic moment of 1 Am2 are placed at point O and P respectively. The distance between OP is 1 meter... In a uniform magnetic field, the magnetic needle has a magnetic moment 9.85$$\times$$10$$-$$2 A/m2 and moment of inertia 5$$\times$$10$$-$6 kg m2....
A circular conducting coil of radius 1 m is being heated by the change of magnetic field $$\overrightarrow B$$ passing perpendicular to the plane in ...
The value of aluminium susceptibility is 2.2 $$\times$$ 10$$-$$5. The percentage increase in the magnetic field if space within a current carrying tor...
A radiation is emitted by 1000W bulb and it generates an electric field and magnetic field at P, placed at a distance of 2m. The efficiency of the bul...
An electromagnetic wave of frequency 3 GHz enters a dielectric medium of relative electric permittivity 2.25 from vacuum. The wavelength of this wave ...
An electromagnetic wave of frequency 5 GHz, is travelling in a medium whose relative electric permittivity and relative magnetic permeability both are...
Two concentric circular coils, C1 and C2 are placed in the XY plane. C1 has 500 turns, and a radius of 1 cm. C2 has 200 turns and radius of 20 cm. C2 ...
A galvanometer coil has 500 turns and each turn has an average area of 3 $$\times$$ 10–4 m2 . If a torque of 1.5 Nm is required to keep this coil pa...
A circular coil of radius 10 cm is placed in a uniform magnetic field of 3.0 $$\times$$ 10–5 T with its plane perpendicular to the field initially. ...
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