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Two thin dielectric slabs of dielectric constants $K_1$ and $K_2$ ($K_1 < K_2$) are inserted between plates of a parallel plate capacitor, as shown in the figure. The variation of electric field $E$ between the plates with distance $d$ as measured from the plate P is correctly shown by:
The ratio of contributions made by the electric field and magnetic field components to the intensity of an electromagnetic wave is: ($c$ = speed of electromagnetic waves)
A small sphere of radius $r$ falls from rest in a viscous liquid. As a result, heat is produced due to the viscous force. The rate of production of heat when the sphere attains its terminal velocity is proportional to:
The ratio of the magnitude of the magnetic field and electric field intensity of a plane electromagnetic wave in free space of permeability $\mu_0$ and permittivity $\varepsilon_0$ is: (Given that $c=$ velocity of light in free space)
A capacitor of 2 μF is charged as shown in the figure. When the switch S is turned to position 2, the percentage of its stored energy dissipated is:
An EM wave is propagating in a medium with a velocity $\vec{v} = v\hat{i}$. The instantaneous oscillating electric field of this EM wave is along the $+y$ axis. The direction of the oscillating magnetic field of the EM wave will be along:
A parallel plate air capacitor is charged to a potential difference of $V$ volts. After disconnecting the charging battery, the distance between the plates of the capacitor is increased using an insulating handle. As a result the potential difference between the plates:
A capacitor is charged by a battery. The battery is removed and another identical uncharged capacitor is connected in parallel. The total electrostatic energy of the resulting system
An electron of mass $m$ and charge $e$ is accelerated from rest through a potential difference $V$ in vacuum. The final speed of the electron will be:
Match List - I with List - II: **List - I (Electromagnetic waves)** (a) AM radio waves (b) Microwaves (c) Infrared radiation (d) X-rays **List - II (Wavelength)** (i) $10^{-10} \text{ m}$ (ii) $10^{2} \text{ m}$ (iii) $10^{-2} \text{ m}$ (iv) $10^{-4} \text{ m}$
A conducting sphere of radius R is given a charge Q. The electric potential and the electric field at the centre of the sphere respectively are:
The equivalent capacitance of the arrangement shown in the figure is:
If $R$ is the radius of the earth and $g$ is the acceleration due to gravity on the earth surface. Then the mean density of the earth will be:
The minimum energy required to launch a satellite of mass $m$ from the surface of the earth of mass $M$ and radius $R$ in a circular orbit at an altitude of $2R$ from the surface of the earth is:
The magnetic field in a plane electromagnetic wave is given by: $B_y = 2 \times 10^{-7} \sin(\pi \times 10^3x + 3\pi \times 10^{11}t) \text{ T}$. The wavelength is:
An electric dipole of moment $\vec{p}$ is lying along a uniform electric field $\vec{E}$. The work done in rotating the dipole by $90^{\circ}$ is:
An electric dipole is placed at an angle of 30° with an electric field intensity 2×10⁵ N/C. It experiences a torque equal to 4 N m. The charge on the dipole, if the dipole length is 2 cm, is:
In a region, the potential is represented by V(x,y,z) = 6x - 8xy - 8y + 6yz, where V is in volts and x, y, z are in meters. The electric force experienced by a charge of 2 coulomb situated at point (1, 1, 1) is
Zener diode works:
Two condensers, one of capacity $C$ and the other of capacity $C/2$ are connected to a $V$ volt battery, as shown in the figure. The energy stored in the capacitors when both condensers are fully charged will be: