How can we communicate by electromagnetic wave ?

 

COMMUNICATING  BY ELECTROMAGNETIC WAVES? 

Radio and television signals travel through space as electromagnetic waves this waves are transmitted by radio and television stations the signals are fixed a by the antenna of your radio or television set the radio or television set turns a signal into sound and picture.

RADIO 

The transmitted at a radio station stains out a radio wave call the career wave the signal produced by the microphones in the reduce to Diu is mixed with the career with the mixing causes the career way to vary in strength or frequency as a microphone signal where is the mixing process is called modulation when the career way passes over the antenna of radio receiver it produces a week electrical signal in antenna the circuit in the radio detect the signal and separate the career signal from the sound signal the sound signal is Dell amplified and fed  to the loudspeaker. 

How can the spacecraft  send message to Earth from like moon , Mars and Venus  this place are very long distance  from earth  

how they sent signals?

August 25th 1989 the voyager 2 space Probe flew  within 3000 miles( 4800 km )of the planet Neptune 2750 million miles( 4400 million km)  from earth its radius signal to 4 hours and 6 minute recharge the signals were transmitted at the same power as a refrigerator light bulb by the time the signals had reached the earth their strength was 20000 million times Weaker than the current from a tiny watch battery yet this week signal would be picked up by receiver on earth and turn to scanning picture of Neptune.

TELEVISION 

In addition to sound signal a television wave carries Earth pictures signal which is produced by the camera in the television Studio when the way falls on the antenna of the television set an electrical signal is produced which goes to the television set the circuit in a television receiver separate the sound and picture signal from the career wave the sound signal is sent to the loudspeaker and the picture signal is sent to the picture to inside the picture tube a beam of electrons is fired in the line it was screen the electron beam is controlled by the fix the signal and make the screen blow to form the picture.

                     THANK YOU FOR READING 

PLS GO THROUGH  THIS LINK  https://learniculture.blogspot.com/2022/10/things-and-facts-misremembered-by.html