Hey! guys, this radio station FM 147, and our topic for today is radio waves! this is a range of electromagnetic waves with a frequency or wavelength suitable for communication (long wavelength)
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| apollo.lsc.vsc.edu/classes/met130/notes/chapter/ionz.html |
Frenquency Range: 100 Hz -- 1000000 Hz
Wavelength Range: 1m -- 1000m
Check out this website for some more fun and explore more types radio waves!
Radio waves are so common in our daily life, and here are some wave sources:
1) mobile ( mobile phones emit and receive radio waves and carry out informations)
2) Antena (receive information carried by radio wavs from long distance or outer space)
3) Satellites (the songs from the satellites station will be carried by radio waves to your car)
4) Even Galaxy!!
5) and more... (there are so many things in our life that will emit or receive radio waves, can you name one? please comment your waves source :)
now it's time to hear some Applications of radio waves!
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| phet.colorado.edu.e.simulation/radio-waves |
Radio waves are so useful in our daily life, but do we really know where is radio wave?
and what are some real application of radio wave? If you don't, that's fine, because We. Are.
Going. To. Find. Out!
- carry informations
- transmitting datas and code
- Radar, carry information Between Earth and astronauts
- (this works because radio wave has such a long wavelength and only require a little bit of energy and can travel really really far!!)
- Entertainment
A simple example of radio entertainment would be Radio Stations in the car. People listen to music by receiving the informations that were carried on the radio waves. Imagine driving a car without any music or new, wouldn't it be so boring? And that's the time for you to open the radio receiver and enjoy the entertain that radio waves brought us.
Yes! Now, this part is gonna get exciting!
there are so many interesting phenomena related to this wave, and let's find out them one by one
* since the huge wavelength of the radio wave, you can talk to space craft hovering out in space with radio waves!
* Black holes also emits radio waves!
* Supernovae remains, they are the strongest at the longer wavelength. They also have synchrotron radiation, which is forbidden to use...
* And finally! The Mysterious Radio Wave from outer space. No one knows who sent them and no one knows what do they mean. They might just happened to be accident, but more likely, they are from Aliens! With great wavelength, it is possible for some crazy aliens to send information to the space and we are just lucky enough to receive it!
If you wanna know more about the mysterious Radio Waves from outer space, you can go check out this video
if you are still not satisfied and agree that radio waves are so interesting, then check out this webscite! I am sure that it will suprise you
Although Radio Waves are so important and so useful in our daily life, they still contain danger
The radio waves emitted by the mobile phone, if long time using, could cause possible carcinogenic to humans (cancr).
When the radio frequency are high enough, they can break down the tissue in the human body and interfere with the DNA. (use telephone or living beside the radio base can cause tumor or cancer).
how do these invetigations/phenomena show that waves are a form of energy that interacts with mater??
radio waves are electromagnetic waves, they carry energy and hit matter that they exert forces on the charges of the atoms that make up the matter.
Antennas works just because radio waves interact with mater and cause current in the antenna which can be converted into information that was sned by the radio wave (one exapmle would be TV)
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