List of top Physics Questions on Electromagnetic waves

Electromagnetic waves travel in a medium with speed \( 1.5 \times 10^8 \) m/s. The relative permeability of the medium is \( 2.0 \). The relative permittivity will be:
What is an electromagnetic wave? On which factors does its velocity in vacuum depend?
If three sources of sound of frequencies \( (n-1), n, (n+1) \) are vibrated together, the number of beats produced and heard per second respectively are:
The RMS value of the electric field of an electromagnetic wave emitted by a source is \( 660 \) N/C. The average energy density of the electromagnetic wave is:
Which of the following produces electromagnetic waves?
The average value of electric energy density in an electromagnetic wave is: [where \( E_0 \) is the peak value]
The RMS value of the electric field of an electromagnetic wave emitted by a source is \( 660 \) N/C. The average energy density of the electromagnetic wave is:
An alternating current having peak value 14.14 A is used to heat a metal wire. The value of the direct current \(i\) required to produce the same heating effect in the same wire is
Which of the following can be used to produce a propagating electromagnetic wave?
Which type of transmission line accepts the Transverse electromagnetic wave?
The ratio between electric field energy density and magnetic field energy density of an electromagnetic wave, in its region is:
A transmitter of power 10 kW emits radio waves of wavelength 500 m. The number of photons emitted per second by the transmitter is of the order of:
If the radio horizon of a transmitting antenna is 21.6 km, the height of the antenna is:
An electromagnetic wave travels in a medium of relative permeability \(1.3\) and relative permittivity \(2.3\). Then the speed of an electromagnetic wave in that medium is
Eddy currents are produced when
A bar magnet of moment \(0.4 \times 10^{-3} \, {Am}^2\) is kept in a magnetic field of \(2\pi \times 10^{-3} \, {T}\). The magnet makes an angle of \(45^\circ\) with the direction of magnetic field. The torque acting on the magnet is:
The energy equivalent of \(3.2 \, \mu g\) of mass is

The electric field for an electromagnetic wave is given by \( E = 40 \sin(kz - 6 \times 10^8 t) \), where the magnitude of \( E_0 \) is in V/m.
The magnitude of the wave vector \( k \) is 
 

A helicopter has metallic blades with length 4 m extending outward from the central point and rotating at 3 rev/s. If the vertical component of Earth's magnetic field is 40 µT, then the emf induced between the blade tip and the central point is

Two charged particles of the same charge but different masses \(m_1\) and \(m_2\) are projected with the same velocity \(V\) normally into the uniform magnetic field \(B\) as shown in the figure. The maximum separation of the particles is: 

The efficiency of a bulb of power \( 60 \) W is \( 16\% \). The peak value of the electric field produced by the electromagnetic radiation from the bulb at a distance of \( 2 \) m from the bulb is? \[ \left(\frac{1}{4\pi \epsilon_0} = 9 \times 10^9 \text{ Nm}^2\text{C}^{-2} \right) \]
The voltage gain of a common emitter amplifier is 60. If the output and input resistances are 4 k\(\Omega\) and 2 k\(\Omega\) respectively, the power gain of the amplifier is:
The refractive index of medium is 1.8 and its relative permeability is 2.16. The relative permittivity of the medium is (nearly):
A pair of adjacent coils has a mutual inductance of 80 mH. If the current in one coil changes from 10 A to 25 A in a time of 1.5 s, the change of flux linked with the other coil is:
The angle of dip at a place where the vertical and horizontal components of earth's magnetic field become equal is: