List of top Physics Questions on Electromagnetic induction asked in NEET (UG)

પરિમિત પ્રતિરોધવાળું એક વાહક લૂપ \( x-y \) પ્લેન પર આવેલું છે. લૂપનું ક્ષેત્રફળ સમય \( t \) સાથે \( A = A_0(1 + \sin t) \) પ્રમાણે બદલાય છે. લૂપમાં વિસર્જિત થતી પાવરના સમય સાથેના ગુણાત્મક વ્યવહારને સાચી રીતે દર્શાવતો આકૃતિ છે:
Let us consider two solenoids A and B, made from same magnetic material of relative permeability \(µ_r\) and equal area of cross-section. Length of A is twice that of B and the number of turns per unit length in A is half that of B. The ratio of self inductances of the two solenoids, LA : LB is
A step up transformer is connected to an ac mains supply of 220 V to operate at 11000 V, 88 watt. The current in the secondary circuit, ignoring the power loss in the transformer, is

The magnetic engery stored in an inductor of inductance 4μH carrying a current of 2 A is:

The net magnetic flux through any closed surface is:
Two conducting circular loops of radii R1 and R2 are placed in the same plane with their centers coinciding. If R1 > > R2, the mutual inductance M between them will be directly proportional to
A 800 turn coil of effective area 0.05 $m^2$ is kept perpendicular to a magnetic field $5\times 10^{-5}$ T. When the plane of the coil is rotated by $90^\circ$ around any of its coplanar axis in 0.1 s, the emf induced in the coil will be
A cycle wheel of radius $0.5\, m$ is rotated with constant angular velocity of $10 \,rad/s$ in a region of magnetic field of $0.1\, T$ which is perpendicular to the plane of the wheel. The $EMF$ generated between its centre and the rim is,
In which of the following devices, the eddy current effect is not used ?
An inductor $20\, mH$, a capacitor $100\, \mu F$ and a resistor $50 \, \Omega$ are connected in series across a source of emf, $V\, = \,10 \,sin\, 314\, t$. The power loss in the circuit is
A long solenoid of diameter $0.1\, m$ has $2 \times 10^4$ turns per meter. At the centre of the solenoid, a coil of $100$ turns and radius $0.01\, m$ is placed with its axis coinciding with the solenoid axis. The current in the solenoid reduces at a constant rate to $0\,A$ from $4\, A$ in $0.05 \,s$. If the resistance of the coil is $10\pi^2 \Omega$ . the total charge flowing through the coil during this time is :
A long solenoid has $1000$ turns. When a current of $4\,A$ flows through it, the magnetic flux linked with each turn of the solenoid is $4 \times 10^{-3} \, Wb$. The self-inductance of the solenoid is :
A uniform magnetic field is restricted within a region of radius $r$. The magnetic field changes with time at a rate $\frac{d \vec{B}}{dt}$. Loop $1$ of radius $R > r$ enclosed the region $r$ and loop $2$ of radius $R$ is outside the region of magnetic field as shown in the figure below. Then the e.m.f. generated is
A resistance 'R' draws power 'P' when connected to an AC source. If an inductance is now placed in series with the resistance, such that the impedance of the circuit becomes 'Z', the power drawn will be
A thin semicircular conducting ring (PQR) of radius 'r' is falling with its plane vertical in a horizontal magnetic field B, as shown in figure. The potential difference developed across the ring when its speed is v, is:
A thin semicircular conducting ring (PQR) of radius 'r'
A wire loop is rotated in magnetic field. The frequency of change of direction of the induced e.m.f. is :
In a coil of resistance 10 Ω, the induced current developed by changing magnetic flux through it, is shown in figure as a function of time. The magnitude of change in flux through the coil in weber is
In a coil of resistance 10 Ω, the induced current developed by changing magnetic flux through it, is shown in figure as a function of time.
A conducting circular loop is placed in a uniform magnetic field $0.04\, T$ with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at $2\, mm/s.$ The induced emf in the loop when the radius is $2\, cm$ is
A rectangular, a square, a circular and an elliptical loop, all in the $( x - y )$ plane, are moving out of a uniform magnetic field with a constant velocity, $\overrightarrow{ V }= v \cdot \hat{ i }$. The magnetic field is directed along the negative z-axis direction. The induced emf, during the passage of these loops, come out of the field region, will not remain constant for:
A circular disc of radius 0.2 meter is placed in a uniform magnetic field of induction $\frac{1}{\pi}\big(\frac{Wb}{m^2}\big)$ in such a way that its axis makes an angle of 60$^{\circ}$ with $\overrightarrow{B}$ . The magnetic flux linked with the disc is
A galvanometer acting as a voltmeter will have
A coil of 40 henry inductance is connected in series with a resistance of 8 ohms and the combination is joined to the terminals of a 2-volt battery. The time constant of the circuit is
The primary winding of a transformer has 500 turns whereas its secondary has 5000 turns. The primary is connected to an A.C. supply 20 V, 50 Hz. The secondary will have an output of
A magnetic field of $2\times 10^{-2}$T acts at right angles to a coil of area 100 $cm^2$, with 50 turns. The average e.m.f. induced in the coil is 0.1 V, when it is removed from the field in t sec. The value of t is