The time period of oscillation of a simple pendulum of length L suspended from the roof of a vehicle, which moves without friction down an inclined plane of inclination α, is given by :
Physicselectromagnetic-waves2022easy
An EM wave propagating in x-direction has a wavelength of 8 mm. The electric field vibrating y-direction has maximum magnitude of 60 Vm−1. Choose the correct equations for electric and magnetic fields if the EM wave is propagating in vacuum :
Physicselectromagnetic-waves2022easy
A radar sends an electromagnetic signal of electric field (E0) = 2.25 V/m and magnetic field (B0) = 1.5 × 10−8 T which strikes a target on line of sight at a distance of 3 km in a medium. After that, a part of signal (echo) reflects back towards the radar with same velocity and by same path. If the signal was transmitted at time t = 0 from radar, then after how much time echo will reach to the radar?
Physicselectromagnetic-waves2022easy
Given below are two statements :
Statement I : A time varying electric field is a source of changing magnetic field and vice-versa. Thus a disturbance in electric or magnetic field creates EM waves.
Statement II : In a material medium, the EM wave travels with speed v = {1 \over {\sqrt {{\mu _0}{ \in _0}} }}. In the light of the above statements, choose the correct answer from the options given below.
Physicselectromagnetic-waves2022easy
Match List-I with List-II :
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List - I
List - II
(a)
Ultraviolet rays
(i)
Study crystal structure
(b)
Microwaves
(ii)
Greenhouse effect
(c)
Infrared rays
(iii)
Sterilizing surgical instrument
(d)
X-rays
(iv)
Radar system
Choose the correct answer from the options given below :
Physicselectromagnetic-waves2022medium
If Electric field intensity of a uniform plane electromagnetic wave is given as E = - 301.6\sin (kz - \omega t){\widehat a_x} + 452.4\sin (kz - \omega t){\widehat a_y}{V \over m}. Then magnetic intensity 'H' of this wave in Am−1 will be :
[Given : Speed of light in vacuum c=3×108 ms−1, Permeability of vacuum μ0=4π×10−7 NA−2]
Physicselectromagnetic-waves2022easy
In free space, an electromagnetic wave of 3 GHz frequency strikes over the edge of an object of size {\lambda \over {100}}, where λ is the wavelength of the wave in free space. The phenomenon, which happens there will be :
Physicselectromagnetic-waves2022easy
Which is the correct ascending order of wavelengths?
Physicselectromagnetic-waves2022easy
The electromagnetic waves travel in a medium at a speed of 2.0 × 108 m/s. The relative permeability of the medium is 1.0. The relative permittivity of the medium will be :
Physicselectromagnetic-waves2022medium
The electric field in an electromagnetic wave is given by E = 56.5 sin ω(t − x/c) NC−1. Find the intensity of the wave if it is propagating along x-axis in the free space.
(Given : ε0 = 8.85 × 10−12C2N−1m−2)
Physicselectromagnetic-waves2022medium
An electric bulb is rated as 200 W. What will be the peak magnetic field at 4 m distance produced by the radiations coming from this bulb? Consider this bulb as a point source with 3.5% efficiency.
Physicselectromagnetic-waves2022medium
A plane electromagnetic wave travels in a medium of relative permeability 1.61 and relative permittivity 6.44. If magnitude of magnetic intensity is 4.5 × 10−2 Am−1 at a point, what will be the approximate magnitude of electric field intensity at that point?
(Given : Permeability of free space μ0 = 4π× 10−7 NA−2, speed of light in vacuum c = 3 × 108 ms−1)
Physicselectromagnetic-waves2022easy
An expression for oscillating electric field in a plane electromagnetic wave is given as Ez = 300 sin(5π× 103x − 3π× 1011t) Vm−1
Then, the value of magnetic field amplitude will be :
(Given : speed of light in Vacuum c = 3 × 108 ms−1)
Physicselectromagnetic-waves2022easy
The rms value of conduction current in a parallel plate capacitor is 6.9μA. The capacity of this capacitor, if it is connected to 230V ac supply with an angular frequency of 600rad/s, will be :
Physicselectromagnetic-waves2022easy
Light wave travelling in air along x-direction is given by Ey=540sinπ×104(x−ct)Vm−1. Then, the peak value of magnetic field of wave will be (Given c = 3 × 108 ms−1)
Physicselectromagnetic-waves2022medium
The magnetic field of a plane electromagnetic wave is given by :
B=2×10−8sin(0.5×103x+1.5×1011t)j^T.
The amplitude of the electric field would be :
Physicselectromagnetic-waves2022medium
The oscillating magnetic field in a plane electromagnetic wave is given by
By=5×10−6sin1000π(5x−4×108t)T. The amplitude of electric field will be :
Physicselectromagnetic-waves2022medium
A velocity selector consists of electric field E=Ek^ and magnetic field B=Bj^ with B=12mT. The value of E required for an electron of energy 728eV moving along the positive x-axis to pass undeflected is :
(Given, mass of electron =9.1×10−31kg )
Physicselectromagnetic-waves2022medium
A beam of light travelling along X-axis is described by the electric field Ey=900sinω(t−x/c). The ratio of electric force to magnetic force on a charge q moving along Y-axis with a speed of 3×107ms−1 will be :
(Given speed of light =3×108ms−1)
Physicselectromagnetic-waves2022easy
Identify the correct statements from the following descriptions of various properties of electromagnetic waves.
(A) In a plane electromagnetic wave electric field and magnetic field must be perpendicular to each other and direction of propagation of wave should be along electric field or magnetic field.
(B) The energy in electromagnetic wave is divided equally between electric and magnetic fields.
(C) Both electric field and magnetic field are parallel to each other and perpendicular to the direction of propagation of wave.
(D) The electric field, magnetic field and direction of propagation of wave must be perpendicular to each other.
(E) The ratio of amplitude of magnetic field to the amplitude of electric field is equal to speed of light.
Choose the most appropriate answer from the options given below :