Phone means………….
c) mobile
b) light
c) sound
d) all of these
It
carries a radio transmitter and receiver inside it and sends and receives a
message in the form of radio waves
a) fax machine
b) computer
c) photo phone
d) cell phone
The medium which sends information from source to receiver is called……..
a) transmission channel
b) transmitter
c) receiver
d) optic fiber
In radio the transmitter receives the massage, encodes into a:
a) ultrasound waves
b) Radio waves
c) Electrical signals
d) sine wave
A fax machine scans a documents and changes the dark and light parts into:
a) ultrasound waves
b) Radio wave
c) electrical signals
d) infra-red rays
The first T.V relay station called Telstar was released in space in…….
a) 1952
b) 1962
c) 1972
d) 1982
