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Two astronauts are floating in a gravity free space after having lost contact with their spaceship. The two will:
An emf is generated by an ac generator having 100 turn coil, of loop area 1 m². The coil rotates at a speed of one revolution per second and placed in a uniform magnetic field of 0.05 T perpendicular to the axis of rotation of the coil. The maximum value of emf is:
A thin conducting ring of radius R is given a charge +Q. The electric field at the centre O of the ring due to the charge on the part AKB of the ring is E. The electric field at the centre due to the charge on the part ACDB of the ring is:
The electric field at the surface of a black box indicates that the net outward flux through the surface of the box is $8.0 \times 10^3$ Nm$^2$/C. What is the net charge inside the box?
To produce an instantaneous displacement current of $2 \text{ mA}$ in the space between the parallel plates of a capacitor of capacitance $4 \text{ }\mu\text{F}$, the rate of change of applied variable potential difference $\left(\frac{dV}{dt}\right)$ must be:
A parallel-plate capacitor of area A, plate separation d, and capacitance C is filled with four dielectric materials having dielectric constants k₁, k₂, k₃ and k₄ as shown in the figure below. If a single dielectric material is to be used to have the same capacitance C in this capacitor, then its dielectric constant k is given by:
One mole of an ideal diatomic gas undergoes a transition from A to B along a path AB as shown in the figure. The change in internal energy of the gas during the transition is:
A system has two charges, q_A = 2.5 × 10⁻⁷ C and q_B = -2.5 × 10⁻⁷ C, located at points A: (0, 0, -15 cm) and B: (0, 0, +15 cm) respectively. The electric dipole moment of the system is:
Which colour of the light has the longest wavelength?
A parallel plate air capacitor has capacitance $C$, the distance of separation between plates is $d$ and potential difference $V$ is applied between the plates. The force of attraction between the plates of the parallel plate air capacitor is:
The magnetic field of a plane electromagnetic wave is given by, $\vec B=3\times10^{-8}\cos(1.6\times10^3x+48\times10^{10}t)\hat j \text{ T}$. The associated electric field will be:
The equivalent capacitance of the combination shown in the figure is:
A point charge causes an electric flux of $-1.0 \times 10^3$ Nm$^2$/C to pass through a spherical Gaussian surface of 10.0 cm radius centered on the charge. If the radius of the Gaussian surface were doubled, how much flux would pass through the surface?
For a plane electromagnetic wave propagating in the $x$-direction, which one of the following combinations gives the correct possible directions for the electric field ($\mathbf{E}$) and magnetic field ($\mathbf{B}$) respectively?
The figure below shows tracks of three charged particles in a uniform electrostatic field. Which particle has the highest charge to the mass ratio?
Four point charges $q_A = 2 \mu\text{C}$, $q_B = -5 \mu\text{C}$, $q_C = 2 \mu\text{C}$, and $q_D = -5 \mu\text{C}$ are located at the corners of a square ABCD of side 10 cm. The force on a charge of $1 \mu\text{C}$ placed at the centre of the square is:
The electric potential at a point $(x, y, z)$ is given by $V = -x^2y - xz^3 + 4$. The electric field $\vec{E}$ at that point is:
A point charge of $2.0 \, \mu\text{C}$ is at the center of a cubic Gaussian surface $9.0 \, \text{cm}$ on edge. What is the net electric flux through the surface?
The electric field associated with an electromagnetic wave in vacuum is given by $E = 40 \cos(kz - 6 \times 10^8 t)$, where $E$, $z$, and $t$ are in volt/m, meter, and second respectively. The value of the wave vector $k$ would be:
When light propagates through a material medium of relative permittivity, $\varepsilon_r$ and relative permeability, $\mu_r$, the velocity of light, $v$ is given by: ($c$ = velocity of light in vacuum)