JEE Main Physics — Electromagnetism previous year questions with solutions.
Two parallel, long wires are kept $0.20m$ apart in vacuum, each carrying current of $xA$ in the same direction. If the force of attraction per meter of each wire is $2\times {10}^{-6}N$, then the value of $x$ is approximately
In meter bridge experiment for measuring unknown resistance '$S$', the null point is obtained at a distance $30\mathrm{cm}$ from the left side as shown at point $D$. If $R$ is $5.6k\Omega$, then the value of unknown resistance '$S$' will be _____ $\Omega$. 
The magnetic field of a plane electromagnetic wave is given by $\vec{B}=2\times {10}^{-8}\mathrm{sin}(0.5\times {10}^{3}x+1.5\times {10}^{11}t)\hat{j}T$. The amplitude of the electric field would be
Two point charges +q and -q are placed at distance d apart. The electric field at the midpoint of the line joining them is:
A bar magnet having a magnetic moment of $2.0\times {10}^{5}J{T}^{-1}$, is placed along the direction of uniform magnetic field of magnitude $B=14\times {10}^{-5}T$. The work done in rotating the magnet slowly through $60^{\circ}$ from the direction of field is
In a series LCR circuit, the inductance, capacitance and resistance are $L=100\mathrm{mH}$, $C=100\mu F$and $R=10\Omega$ respectively. They are connected to an $\mathrm{AC}$ source of voltage $220V$ and frequency of $50\mathrm{Hz}$. The approximate value of current in the circuit will be _____ $A$. 
If the electric potential at any point $(x,y,z)m$ in space is given by $V=3{x}^{2}$ volt. The electric field at the point $(1,0,3)m$ will be :
A small square loop of wire of side $l$ is placed inside a large square loop of wire $L(L\gg l)$. Both loops are coplanar and their centres coincide at point $O$ as shown in figure. The mutual inductance of the system is 
A telegraph line of length $100\mathrm{km}$ has a capacity of $0.01\mu F{\mathrm{km}}^{-1}$ and it carries an alternating current at $0.5$ kilo cycle per second. If minimum impedance is required, then the value of the inductance that needs to be introduced in series is _____ $\mathrm{mH}$. (If $\pi =\sqrt{10}$)
The charge on capacitor of capacitance $15\mu F$ in the figure given below is 
A wire of length $314\mathrm{cm}$ carrying current of $14A$ is bent to form a circle. The magnetic moment of the coil is $A-{m}^{2}$. [Given $\pi =3.14$]
A plane electromagnetic wave travels in a medium of relative permeability $1.61$ and relative permittivity $6.44$. If magnitude of magnetic intensity is $4.5\times {10}^{-2}A{m}^{-1}$ at a point, what will be the approximate magnitude of electric field intensity at that point ? (Given : Permeability of free space ${\mu }_{0}=4\pi \times {10}^{-7}N{A}^{-2}$, speed of light in vacuum $c=3\times {10}^{8}{ms}^{-1}$)
If a charge $q$ is placed at the centre of a closed hemispherical non-conducting surface, the total flux passing through the flat surface would be 
A $72\Omega$ galvanometer is shunted by a resistance of $8\Omega$. The percentage of the total current which passes through the galvanometer is
All resistances in figure are $1\Omega$ each. The value of current '$I$' is $\frac{a}{5}A$. The value of $a$ is _____ . 
For a series $LCR$ circuit, $I$ vs $\omega$ curve is shown  (a) To the left of ${\omega }_{r}$, the circuit is mainly capacitive. (b) To the left of ${\omega }_{r}$, the circuit is mainly inductive. (c) At ${\omega }_{r}$, impedance of the circuit is equal to the resistance of the circuit. (d) At ${\omega }_{r}$, impedance of the circuit is $0$. Choose the most appropriate answer from the options given below.
A positive charge particle of $100\mathrm{mg}$ is thrown in opposite direction to a uniform electric field of strength $1\times {10}^{5}N{C}^{-1}$. If the charge on the particle is $40\mu C$ and the initial velocity is $200{ms}^{-1}$, how much distance it will travel before coming to the rest momentarily
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 ratio of the radii of the circular paths described by the alpha particle and proton is
Two identical thin metal plates has charge ${q}_{1}$ and ${q}_{2}$ respectively such that ${q}_{1}>{q}_{2}$. The plates were brought close to each other to form a parallel plate capacitor of capacitance $C$. The potential difference between them is :
Two resistors are connected in series across a battery as shown in figure. If a voltmeter of resistance $2000\Omega$ is used to measure the potential difference across $500\Omega$ resister, the reading of the voltmeter will be _____ $V$ 
The current in a coil of self inductance $L=2.0H$ is increasing according to the law $i=2\mathrm{sin}({t}^{2})$. Find the amount of energy spent (in $J$) during the period when the current changes from $0$ to $2A$.
Match List - I with List - II. <table class="pyq-table"><tbody><tr><td></td><td>List-I</td><td></td><td>List-II</td></tr><tr><td>(A)</td><td>AC generator</td><td>(I)</td><td>Detects the presence of current in the circuit</td></tr><tr><td>(B)</td><td>Galvanometer</td><td>(II)</td><td>Converts mechanical energy into electrical energy</td></tr><tr><td>(C)</td><td>Transformer</td><td>(III)</td><td>Works on the principle of resonance in AC circuit</td></tr><tr><td>(D)</td><td>Metal detector</td><td>(IV)</td><td>Changes an alternating voltage for smaller or greater value</td></tr></tbody></table>
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 given circular loop from the center on its axis is ${B}_{2}$. The value of $\frac{{B}_{1}}{{B}_{2}}$ will be
A parallel plate capacitor is made up of stair like structure with a plate area A of each stair and that is connected with a wire of length $b$, as shown in the figure. The capacitance of the arrangement is $\frac{x}{15}\frac{{\epsilon }_{0}A}{b}$, The value of $x$ is _____ . 