And Its
What is Electromagnetic Spectrum? The electromagnetic spectrum is a collection of electromagnetic waves arranged according to frequency and wavelength.
How EMR’s are formed Electromagnetic waves are formed when an electric field (which is shown in blue arrows) couples with a magnetic field (which is shown in red arrows).
WHAT ARE WAVES? WHAT IS WAVELENGTH? WAVELENGTH: It is the distance from one point on a wave to the corresponding point on the next consecutive wave. WAVES: Waves are a series of crests and troughs moving past a given reference point.
WHAT ARE ELECTROMAGNETIC WAVES? Static electricity can make your hair stand on end. Magnets can attract certain metals. Radio waves, TV waves and microwaves are all types of electromagnetic waves. However, they differ in wavelength and energy.
POWER DECIMALPREFIXPHONICSYMBOL OF TEN EQUIVALENT terater'aT gigagi'gaG megameg'aM kilokil'ok Scientific Notation
FREQUENCY = the number of cycles per second HERTZ = the unit attached to frequency COMPARISON OF WAVE LENGTHS WITH IN THE ELECTROMAGNETIC SPECTRUM
EMR SPECTRUM CHARACTERISTICS Energy Wavelength Frequency Radio Micro Infra Visible UV X-rays Gamma Waves Waves Red Light Light Rays
Common Hertz Relationships HERTZ TYPE ____________________________________________________________________________________________________ approximately 60 Electrical power _______________________________________________________________________________ (20 k)audio frequencies - human _______________________________________________________________________________ 10 k - 30 Gradio frequencies _______________________________________________________________________________ 540 k kAmplitude Modulation (AM) _______________________________________________________________________________ 88 M -108 M Frequency Modulation (FM) ________________________________________________________________________________ 30 M MVHF - TV (very high frequency) ________________________________________________________________________________ 54 M MCATV (Cable Antenna Television) ________________________________________________________________________________ 300 M M (3 G)UHF - TV (ultra high frequency) ________________________________________________________________________________ 3 G - 30 microwave (super high frequency) ________________________________________________________________________________
F EDERAL C OMMUNICATIONS C OMMISSION Government Agency that Monitors and Controls Mass Communication Industries
WHY USE MICROWAVES FOR COMMUNICATION? Microwaves are good for transmitting information because their energy can penetrate fog, light rain and snow, clouds and smoke.
SATELLITE ORBITS Three basic kinds of orbits: 1) GEOSYNCHRONOUS - also called Geostationary or Synchronous) 2) Asynchronous - used by space shuttle - very low altitude (400 miles) - pass over at different times of the day 3) Polar - low altitude - passes over the earth’s poles on each revolution
References Date obtained: September 21, Date obtained: September 21, _l1/emspectrum.html