The electric field associated with an electromagnetic wave in vacuum is given by E= 40coswhere E, z, and t are in volt/m, meter, and second respectively. The value of wave vector k is:
1. 2.
3. 4. 3
The decreasing order of the wavelength of infrared, microwave, ultraviolet and gamma rays is:
1. | Gamma rays, ultraviolet, infrared, microwaves |
2. | Microwaves, gamma rays, infrared, ultraviolet |
3. | Infrared, microwave, ultraviolet, gamma rays |
4. | Microwave, infrared, ultraviolet, gamma rays |
The electric field of an electromagnetic wave in free space is given by where t and x are in seconds and meters respectively. It can be inferred that
(1) The wavelength is 188.4 m.
(2) The wave number k is 0.33 rad/m.
(3) The wave amplitude is 10 V/m.
(4) The wave is propagating along +x direction
Which one of the following pairs of statements is correct?
1. (3) and (4) 2. (1) and (2)
3. (2) and (3) 4. (1) and (3)
The electric field part of an electromagnetic wave in a medium is represented by :
1. | Moving along y-direction with frequency \(2\pi\times 10^6~Hz\) and wavelength 200 m. |
2. | Moving along +x-direction with frequency \(10^6~Hz\) and wavelength 100 m. |
3. | Moving along +x-direction with frequency \(10^6~Hz\) and wavelength 200 m. |
4. | Moving along - x-direction with frequency \(10^6~Hz\) and wavelength 200 nm. |
Which of the following rays are not electromagnetic waves ?
(a) -rays (b) -rays
(c) Heat rays (d) X-rays
Statement-I: Gamma rays are more energetic than X-rays.
Statement-II: Gamma rays are of nuclear origin but X-rays are produced due to sudden deceleration of high energy electrons while falling on a metal of high atomic number.
(1) If both statement-I and Statement-II are true, and Statement-II is the correct explanation of Statement-I.
(2) If both Statement-I and Statement-II are true but Statement-II is not the correct explanation of Statement-I.
(3) If Statement-I is true but Statement-II is false.
(4) If Statement-I is false but Statement-II is true.
The S.I unit of displacement current is
(1) Henry
(2) Coulomb
(3) Ampere
(4) Farad
An electromagnetic wave going through Vaccum is described by
(1)
(2)
(3)
(4) none of these
An electromagnetic wave going through a medium is given by then
(1)
(2) If Electric field is in Z direction them magnetic field should be in -y direction
(3) Both 'A' and 'B' are correct
(4) Only A is correct
A plane E M wave of frequency 25 MHz travels in free space in the x-direction. At a particular point in space and time then B at the point is
(1)
(2)
(3) 2.1
(4)