science 3&4 (rev)

• "radio waves" are used as a medium for transmitting information between mobile devices. qhen you send message, voice call, a video clip, or a photo, this information is transformed into signals which are then sent through microwave to the nearest cell tower

  cellphones communication
• radio and television signals are radio waves that are produced by making "electrons vibrate". it has a long wavelength capable to transmit sound and picture information over long distances


  radio/television signals
• it is a space-based navigation system that provides geographical position and time information anywhere on or near the earth. it communicates with stations on the ground using radio waves


  global positioning system (GPS)
• it is medical imaging techniques that uses powerful magnets, computer, and radios to make detailed pictures inside yoyr body


  magnetic resonance imaging (mri)
• it is a detection system used to determine the range, angle, or velocity of objects. it can ve used to detect aircraft, ships, and the like.


  RADAR (radio detection and ranging)
• refer to specific kinds of electromagnetic waves and are characterized by long wavelengths ranging between 0.04 and 12 inches, and short frequencies of up to 300GHz. are most suited to transmitting signals that require a large bandwitg and have a wide range of practical applications in cooking, communication, and radar

  microwaves
• microwaves can penetrate the atmosphere of the earth. "microwaves signals are transmitted by an antenna to a satellite which amplifies and re-transmits the signal to an antenna in other parts of the world. this is how we communicate with the rest of the world

  satellite communication
• a "cellohone" is a radio transmitter and receiver that uses microwaves. cellular phones depend on overlapping network of cells. each cell has its tower that receive and sends microwave signals


  terrestrial communication
• the microwave in a microwave over penetrate and agitate the water molecules within the food. thus, they create molecular friction which produces heat what will cook the food

  cooking
• lies beyond the red end of the visible light. it is emitted by all objects the amount and wavelength of radiation depend on temperature

  infrared
• an objects emits only infrared radiation

  below 500°C
• an object glows and emits both infrared and some visible light

  abive 500°C