New Reply

How Data on electromagnetic waves are transmitted ?

 
Share Thread Thread Tools
Aug7-11, 06:45 PM   #1
 
Arrow

How Data on electromagnetic waves are transmitted ?


Hello every one .
We know Radio waves carrying data
When a radio device receives radio waves , It render the waves and we hear sound .

Now my questions are :
1 - How data on electromagnetic waves are transmitted ?

When a electromagnetic wave hit a atom it absorbed by the atom
like this


Then after a short delay another photon is emitted .

2 - What happens to the data at this moment ?

3 - What's the data ? are they atoms ? are they electrons ? are they Community atoms ? or ...... ?
 
PhysOrg.com
PhysOrg
physics news on PhysOrg.com

>> Promising doped zirconia
>> New X-ray method shows how frog embryos could help thwart disease
>> Bringing life into focus
Aug7-11, 08:15 PM   #2
 
Mentor
Blog Entries: 27
Er.. you have a wrong idea on basic E&M, especially on antenna.

Since EM waves (photons) have oscillating E-field, I can detect such waves simply with an antenna. That's what your radio does. One can naively think of it as the oscillating E-field inducing current in an antenna. This current is the transmitted signal. What you are receiving is not due to some atomic excitation.

Zz.
 
Aug7-11, 11:49 PM   #3
 
Recognitions:
Homework Helper Homework Help
To find out how sound information is sent by radio, search about "amplitude modulation" or "frequency modulation", better known as AM and FM.
 
Aug8-11, 12:29 AM   #4
 

How Data on electromagnetic waves are transmitted ?


One could almost think of an old player piano where little bumps at different places make different sounds. You could think of different amplitudes or wavelengths as changing the location of the bump on the roll.
 
Aug8-11, 06:25 PM   #5
 
Recognitions:
Gold Membership Gold Member
Look up antenna, AM and FM radio, electromagnetic radiation, and other similar items on wikipedia. That will explain pretty much everything about this.
 
New Reply
Thread Tools


Similar Threads for: How Data on electromagnetic waves are transmitted ?
Thread Forum Replies
Information transmitted faster than light? General Physics 30
mechanical waves - average power transmitted Introductory Physics Homework 0
Can all electromagnetic waves carry information? General Physics 3
can information be transmitted faster than c in inflationary cosmology? Special & General Relativity 2
Reflected and Transmitted Waves Phase changes Advanced Physics Homework 0