Name the part of the electromagnetic spectrum of wavelength 10-2 m and mention its one application.
in microwave ovens1)in radar communication 2)in microwave ovens
5
Write the following radiations in ascending order in respect of their frequencies ; X-rays, Microwaves, UV rays and radiowaves.
Radiowaves, microwaves, UV-rays and X-rays.
5
Name the EM waves used for studying crystal structure of solids. What is its frequency range?
X-rays frequency range : 1017 Hz to 1020 Hz
5
Which part of electromagnetic spectrum is absorbed from sunlight by ozone layer?
Ultraviolet rays are absorbed from sunlight by ozone layers.
5
Which part of electromagnetic spectrum is used in radar systems? (
Microwave region of electromagnetic spectrum is used in radar systems.
5
A plane electromagnetic wave travels in vacuum along z-direction. What can you say about the direction of electric and magnetic field vectors?
The direction of electric field vector is along X-axis. Magnetic field vector is along Y-axis.
10
How are radio waves produced?
produced by the accelerated motion of charges in conducting wires
10
What are the directions of electric and magnetic field vectors relative to each other and relative to the direction of propagation of electromagnetic waves?
The oscillations of E and B fields are perpendicular to each other as well as to the direction of propagation of the wave.
15
The speed of an electromagnetic wave in a material medium is given by v=1\√με. μ the permeability of the medium and ε its permittivity. How does its frequency change?
Frequency remains unchanged.
10
How are infrared waves produced?Write their one important use.
produced by hot bodies,molecules, used to take photographs in darkness and to study secret writin, also used in physical therapy
15
What is amplitude modulation?
Amplitude modulation is a process by which the wave signal is transmitted by modulating the amplitude of the signal, frequency remains constant.
15
What is the FM?
the modulation of a radio or other wave by variation of its frequency, especially to carry an audio signal, amplitude of carrier wave remain constant
15
what is bandwidth ?
... is the range of frequencies occupied by a modulated radio-frequency signal, usually given in hertz
20
State the name components of the frequency spectrum, determine the frequency of audio signal.
Carrier wave frequency=50 kHz,sidebands, audio signal f=5kHz
20
Determine the wavelength of the carrier wave for this transmission