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Which of the following statements is false for the properties of electromagnetic waves?
The magnetic energy stored in an inductor of inductance $4 \text{ }\mu\text{H}$ carrying a current of $2 \text{ A}$ is:
An ideal inductor-resistor-battery circuit is switched on at $t=0$ s. At time $t$, the current is $i=i_0(1-e^{-t/\tau})$, where $i_0$ is the steady-state value. The time at which the current becomes $0.5i_0$ is: [Given $\ln(2)=0.693$]
The electric field part of an electromagnetic wave in a medium is represented by E_x = 0; E_y = 2.5 \text{ N/C} \cos[(2\pi \times 10^6)t - (\pi \times 10^{-2})x]; E_z = 0. The wave is:
If $\vec{E}$ and $\vec{B}$ represent the electric field vector and magnetic field vector, respectively, in an electromagnetic wave then the direction of EM wave is along:
The electric and magnetic fields of an electromagnetic wave are:
The velocity of electromagnetic radiation in a medium of permittivity $\varepsilon_0$ and permeability $\mu_0$ is given by:
A liquid does not wet the solid surface if the angle of contact is:
In a plane electromagnetic wave travelling in free space, the electric field component oscillates sinusoidally at a frequency of $2.0 \times 10^{10} \text{ Hz}$ and amplitude $48 \text{ V m}^{-1}$. Then the amplitude of the oscillating magnetic field is: (Speed of light in free space $= 3 \times 10^8 \text{ m s}^{-1}$)
Two identical capacitors $C_1$ and $C_2$ of equal capacitance are connected as shown in the circuit. Terminals a and b of the key k are connected to charge capacitor $C_1$ using a battery of emf $V$ volt. Now disconnecting a and b terminals, terminals b and c are connected. Due to this, what will be the percentage loss of energy?
The height at which the weight of a body becomes 1/16th, its weight on the surface of the earth (radius R), is:
Charges $+q$ and $-q$ are placed at points A and B, respectively, which are at a distance $2L$ apart. C is the midpoint between A and B. The work done in moving a charge $+Q$ along the semicircle CRD is:
A barometer is constructed using a liquid (density = 760 kg/m³). What would be the height of the liquid column, when a mercury barometer reads 76 cm? (the density of mercury = 13600 kg/m³)
If the mean free path of atoms is doubled then the pressure of the gas will become:
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:
Four equal charges Q are placed at the four corners of a square of each side is ‘a’. Work done in removing a charge –Q from its centre to infinity is
The electrostatic force between the metal plates of an isolated parallel plate capacitor $C$ having a charge $Q$ and area $A$ is:
Out of the following options which one can be used to produce a propagating electromagnetic wave?
An electromagnetic wave is moving along negative $z$ ($-z$) direction and at any instant of time, at a point, its electric field vector is $3\hat j \text{ V/m}$. The corresponding magnetic field at that point and instant will be: (Take $c=3\times10^8 \text{ ms}^{-1}$)
The dimensions of mutual inductance (M) are: