Radio waves
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What are they?
Radio waves are part of the electromagnetic spectrum. The waves are packets of energy with differing wavelengths, similar to visible light waves, X-rays or Gamma rays but longer. They travel in straight lines like bullets but inside they wiggle up and down.

Are they dangerous?

Radio waves are can be dangerous to humans because they carry free radicals. They can also lead to extreme large temperature rise which in the long term is disastrous. The body's absorption of these radio waves is measured as the Specific Absorption Rate (SAR).
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Where do they come from?
They are transmitted from a radio transmitter. These are found all over the country so the waves can be transmitted everywhere.
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How do we detect them?
We detect them using an antenna.


What can they be used for?
They can be used for AM radio, FM, radio,TV, mobile phones and things like the police.
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In the table below, fill the cells with very brief notes. Use the other pages to gather the information from, and you may want to go outside of this wiki if you really can't find the information here (though I'd be surprised!).


Name
Gamma
X-rays
UV
Visible
IR
Microwaves
Radio
How are they generated?
Stars, super novas, black holes, pulsars, on earth by natural radioactive decay, by nuclear explosions and by lightning in thunderstorms.
X-rays are generated by an X-ray tube, a vacuum tube that uses a high voltage to accelerate the electrons released by a hot cathode to a high speed.
They can come from the sun, but you can get man made lamps for experimental perposes, tanning ect... they produce ultra violet rays, just as the sun does.
They just appear.
They come from everything above absolute zero.
Microwaves are emitted from a number of sources, for instance, in a mobile phone, they are generated by a transmitter chip and an antenna, while in a microwave oven they are generated by a 'magnetron'. They are also released as a form of electromagnetic radiation from large stars
They are transmitted from a radio transmitter. These are found all over the country so the waves can be transmitted everywhere.
How are they detected?
Densely packed crystal blocks
Thin films and photographic plates.
To detect them you can simply use a filtrate this is the cheepest option and used frequently. As well as this you could use a UV dectector.
Our eyes.
We can use such things as night- vision goggles or thermal imaging cameras to detect them.
Because humans cannot detect electromagnetic radiation we need special tools to detect them. If the waves are used for communications we use a reciver to detect them. If we are checking for contamination we can use a gieger tube to test for them.
We detect them using an antenna.
How might they be dangerous?
They are radioactive.
X- rays can damage cells and cause cause cell mutation which can cause cancer or cell death.
It can be dangerous as they damage and kill cells.
We could get blinded.
IR waves carry little damage to humans.
Prolonged exposure to microwaves is known to cause cataracts, which is a clouding of the lens, in your eyes preventing you from seeing clearly. Recent research indicates that microwaves from mobile phones can affect parts of your brain.
Radio waves are can be dangerous to humans because they carry free radicals. They can also lead to extreme large temperature rise which in the long term is disastrous. The body's absorption of these radio waves is measured as the Specific Absorption Rate (SAR).
What are the main or most significant uses?
We can use them to kill cancerous cells and cure some types of cancer with them.
To scan for bone breakages or in dentists.
Can be used for tanning, in a tanning bed or by the sun.
To see things.
A remote control uses light waves just beyond the visible spectrum of light (to change channels on your TV) or for cooking in grills and toasters.
Microwaves cause water and fat molecules to vibrate, which makes the substances hot. Therefore we can use microwaves to cook many types of food. Mobile phones use microwaves, as they can be generated by a small antenna, which means that the phone doesn't need to be very big.Microwaves are also used by fixed traffic speed cameras, and for radar, which is used by aircraft, ships and weather forcasters. The most common type of radar works by sending out bursts of microwaves, detecting the "echoes" coming back from the objects they hit (like a bat uses echo location), and using the time it takes for the echoes to come back to work out how far away the object is. They are also used to transmit data over long distances with satelites.
They can be used for AM radio, FM, radio,TV, mobile phones and things like the police.

Good work. Not the easiest topic to find good material for but you have done well. Not sure if all of the images are useful and they all need explanations or captions - even if they are labelled - to explain why they are there.
Nice formatting on the table.

Well done!
A-

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