### energy | radiation:

Radio wave
* are a form of light and travel at the speed of light
  - kind of electromagnetic radiation, and thus they move at the speed of light
* are a type of electromagnetic wave
  - energy that radiates out from a source, just as light or sound does
  - able to penetrate interstellar dust clouds
  - airwaves
  - also a form of light
  - always there
  - another kind of electromagnetic wave
  - capable of supporting mobile communication between rooms
  - carefully controlled electromagnetic radiation
  - current alternating millions of times per second
  - examples of light with a long wavelength, low frequency, and low energy
  - just like light waves, but much bigger
  - long wave electromagnetic waves
  - merely one type of electromagnetic wave
* are much faster, longer, and more frequent than ocean waves, however
  - slower
  - of even lower frequency than visible light
  - part of a general class of waves known as electromagnetic waves
  - photons
  - quite different from ionizing or nuclear radiation
* are used for many things today
  - to send and receive communications
  - very powerful and travel great distances through the universe
  - well known for their ability to transmit radio and television signals
* can also be very wide.
* can be anything from a fraction of a millimetre to kilometres long
  - several feet to several miles long
  - cause unintended motion of power wheelchairs or scooters
  - have wavelengths measured in hundreds of meters
  - induce signals on wires
  - propagate for kilometres through ice
  - reflect off of surfaces, such as layers of ionized gases in the ionosphere
  - travel where there are no air molecules
* carry data between the computers, wherever in the house they happen to be
  - the noises to land
* come from the lowest energy electrons.
* consist of an oscillating electromagnetic field, as do light waves.
* contain both electric and electromagnetic fields.
* diffracted by such objects can affect the strength of the received signal.
* do strange things from time to time.
* have a much longer wavelength that light waves
  - tendency to loose their quality with distance
  - difficulty penetrating physical structures
  - frequencies lower than visible and infrared light on the electromagnetic spectrum
  - large wavelengths from a centimetre to tens of thousands of metres
* have longer wavelength than light, which has a longer wavelength than X-rays
  - wavelengths than gamma rays
  - longest wavelength
* have much longer wavelengths and lower frequencies than do visible light waves
  - than light and therefore diffract more
  - no boundaries
  - the longest wavelengths in the electromagnetic spectrum
  - trouble penetrating metal objects and trees
  - two important characteristics that change
* have very long wavelengths and travel through clouds easily
  - wavelengths, low frequency and hence, low energy
* induce current in certain objects.
* is radiation
* make electricity flow up and down in the antenna wire like that
  - radio wave electricity flow between the antenna wire and the ground wire
* pass through our atmosphere very easily.
* pour in from two regions called radio lobes on either side of the galaxy's dust lanes.
* produced on Earth are mostly manmade and are often at one specific frequency.
* range from a few kilohertz to several gigahertz
  - the size of people to buildings
* reflect off of surfaces the same way that water waves do.
* require higher energy than X-rays.
* travel across the crystal radio antenna all the time.
* travel at lightspeed, and the moon little over one light-second from Earth
  - far, are invisible to humans and are easy to detect even when they are faint
* travel through prana
  - space with the least absorption or distortion
  - vast distances through space and are relatively easy to detect
  - very fast
+ Radiation: Basic physics ideas :: Wave physics :: Nuclear physics
  * This is the kind of electromagnetic radiation with the highest wavelength. Radio waves are used to send and receive communications.
+ Radio wave, Uses: Wave physics :: Radio
  * Radio waves are used for many things today. They broadcast radio and television, communicate with satellites, let mobile phones communicate with each other, make radar systems, and allow computers to share information without wires.