Physics
Magnetism
Previous Years Questions

Which one of the following options represents the magnetic field $\vec{B}$ at $\mathrm{O}$ due to the current flowing in the given wire segments lying...
A small circular loop of area $A$ and resistance $R$ is fixed on a horizontal $x y$-plane with the center of the loop always on the axis $\hat{n}$ of ...
When the dipole m is placed at a distance r from the center of the loop (as shown in the figure), the current induced in the loop will be proportional...
The work done in bringing the dipole from infinity to a distance r from the center of the loop by the given process is proportional to
A circular coil of radius R and N turns has negligible resistance. As shown in the schematic figure, its two ends are connected to two wires and it is...
A light disc made of aluminium (a nonmagnetic material) is kept horizontally and is free to rotate about its axis as shown in the figure. A strong mag...
A symmetric star shaped conducting wire loop is carrying a steady state current $${\rm I}$$ as shown in the figure. The distance between the diametric...
In which case will the particle move in a straight line with constant velocity?
In which case will the particle describe a helical path with axis along the positive $$z$$ direction?
In which case would the particle move in a straight line along the negative direction of $$y$$-axis (i.e., move along $$- \widehat y$$)?
When d $$\approx$$ a but wires are not touching the loop, it is found that the net magnetic field on the axis of the loop is zero at a height h above ...
Consider d >> a, and the loop is rotated about its diameter parallel to the wires by 30$$^\circ$$ from the position shown in the below figure. If the ...
The magnitude of the induced electric field in the orbit at any instant of time during the time interval of the magnetic field change is
The change in the magnetic dipole moment associated with the orbit, at the end of the time interval of the magnetic field change, is
A loop carrying current $$l$$ lies in the xy-plane as shown in the figure. The unit vector $$\widehat k$$ is coming out of the plane of the paper. The...
An infinite long hollow conducting cylinder with inner radius R/2 and outer radius R carries a uniform current density along its length. The magnitude...
A long insulated copper wire is closely wound as a spiral of N turns. The spiral has inner radius a and outer radius b. The spiral lies in the xy-plan...
A thin flexible wire of length L is connected to two adjacent fixed points and carries a current I in the clockwise direction, as shown in the figure....
In the graph below, the resistance R of a superconductor is shown as a friction of its temperature T for two different magnetic fields B1 (solid line)...
A superconductor has Tc(0) = 100 K. When a magnetic field of 7.5 T is applied, its Tc decreases to 75 K. For this material, one can definitely say tha...

## MCQ (More than One Correct Answer)

Two concentric circular loops, one of radius R and the other of radius 2R, lie in the xy-plane with the origin as their common center, as shown in the...
A long straight wire carries a current, I = 2 ampere. A semi-circular conducting rod is placed beside it on two conducting parallel rails of negligibl...
Two infinitely long straight wires lie in the $$xy$$-plane along the lines $$x = \pm R.$$ The wire located at $$x = + R$$ carries a constant current...
A uniform magnetic field $$B$$ exist in the region between $$x=0$$ and $$x = {{3R} \over 2}$$ (region $$2$$ in the figure) pointing normally into the ...
In a thin rectangular metallic strip a constant current I flows along the positive x-direction, as shown in the figure. The length, width and thicknes...
In a thin rectangular metallic strip a constant current I flows along the positive x-direction, as shown in the figure. The length, width and thicknes...
A conductor (shown in the figure) carrying constant current I is kept in the x-y plane in a uniform magnetic field B. If F is the magnitude of the tot...
A steady current I flows along an infinitely long hollow cylindrical conductor of radius R. This cylinder is placed coaxially inside an infinite solen...
A particle of mass M and positive charge Q, moving with a constant velocity $${\overrightarrow u _1} = 4\widehat i$$ ms$$-$$1 enters a region of unifo...
Consider the motion of a positive point charge in a region, there are simultaneous uniform electric and magnetic fields $$\overrightarrow E = {E_0}\w... An electron and a proton are moving on straight parallel paths with same velocity. They enter a semi-infinite region of uniform magnetic field perpend... ## Numerical An$$\alpha$$-particle (mass 4 amu) and a singly charged sulphur ion (mass 32 amu) are initially at rest. They are accelerated through a potential V a... A moving coil galvanometer has$$50$$turns and each turn has an area$$2 \times {10^{ - 4}}\,{m^2}.$$The magnetic field produced by the magnet insid... In the$$xy$$-plane, the region$$y > 0$$has a uniform magnetic field$${B_1}\widehat k$$and the region$$y < 0$$has another uniform magnetic... Two parallel wires in the plane of the paper are distance X0 apart. A point charge is moving with speed u between the wires in the same plane at a dis... A cylinder cavity of diameter a exists inside a cylinder of diameter 2a as shown in the figure. Both the cylinder and the cavity are infinitely long. ... A long circular tube of length 10 m and radius 0.3 m carries a current I along its curved surface as shown. A wire-loop of resistance 0.005$$\Omega...
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