We can receive data either through our television aerial or down our telephone lines and display this data on our television screen. What is the general name given to this process?
View data
Tele text
Tele software
Video text
Long distance short-wave radio broadcasting uses :
Ground wave
Ionospheric wave
Direct wave
Sky wave
For television broadcasting, the frequency employed is normally :
30-300 MHz
30-300 GHz
30-300 KHz
30-300 Hz
The radio waves of frequency 300 MHz to 3000 MHz belong to :
High frequency band
Very high frequency band
Ultra high frequency band
Super high frequency band
A laser is a coherent source because it contains :
Many wavelengths
Uncoordinated wave of a particular wavelength
Coordinated wave of many wavelengths
Coordinated waves of a particular wavelength
The maximum distance upto which TV transmission from a TV tower of height h can be received is proportional to :
h1/2
h
h3/2
h2
A laser beam is used for carrying out surgery because it :
Is highly monochromatic
Is highly coherent
Is highly directional
Can be sharply focused
Consider telecommunication through optical fibres. Which of the following statements is not true?
Optical fibres may have homogeneous core with a suitable cladding
Optical fibres can be of graded refractive index
Optical fibres are subject to electromagnetic interference from outside
Optical fibres have extremely low transmission loss
Television signals on earth cannot be received at distances greater than 100 km from the transmission station. The reason behind this is that :
The receiver antenna is unable to detect the signal at a distance greater than 100 km
The TV programme consists of both audio and video signals
The TV signals are less powerful than radio signals
The surface of earth is curved like a sphere
Advantage of optical fibre :
High bandwidth and EM interference
Low bandwidth and EM interference
High band width, low transmission capacity and no EM interference
High bandwidth, high data transmission capacity and no EM interference