ELECTROMAGNETIC SPECTRUM

• electric charges in motion produce an electric current.
• magnetism is produced due to changing electric current
• He is an English scientist who noticed that electrical fields and magnetic fields that propagate in space combined together to form electromagnetic waves, which leads to a result of him developing a scientific theory that explains electromagnetic waves.

  James Clerk Maxwell
• A changing magnetic field induced a changing electric field or vice versa
• James Clerk Maxwell said that Electromagnetic waves have the same measurement as the speed of the light, making light an electromagnetic wave itself.
• Light is an example of an electromagnetic wave
• Heinrich Hertz was the one who used and verified Maxwell's theories for him to understand the production, generation, and reception of radio waves.
• The frequency of a radio wave is expressed in a unit (Hertz (Hz)) of one cycle per second
• The discovery of the existence of radio waves was in the late 1880's
• Heinrich Hertz was the one who conducted an experiment where he used two rods at a distance from each other, which serves as the receiver and transmitter
• Who is this man? James Clerk Maxwell

  
• Who is this man? Heinrich Hertz

  
• Electric fields originated on positive charges (Anode) and terminated to negative charges (Cathode)
• Anode and Cathode can be determined by applying the Coulumb's Law of Magnetism
• Coulumb's Law of Magnetism where the force of attraction is directly proportional to the square of the distance between them.
• The idea that A changing to magnetic field B induces an electromotive force, thus it produces an electric field was derived from Faraday's Law of Electromagnetic Induction
• Ampere's Law explains that magnetic fields are produced through the acceleration of charges
• The magnetic field oscillates perpendicularly to the electric field and moves in the direction of the propagation of the wave.
• All electromagnetic waves can travel to any medium, unlike other waves like mechanical wave
• Magnetic field lines form closed loops
• PARTS OF AN ELECTROMAGNETIC WAVE: Propagation Vector or Propagation Direction, Electric Field, Magnetic Field, Wavelength, Amplitude, Crest, Trough

  
• The Propagation Vector or Propagation Direction is the direction in which energy of the wave is moving
• The Electric Field is a region of space around an electrically charged particle or object in which an electric charge would feel force.
• The Magnetic Field is the region around a magnetic material or a moving electric charge within which the force of magnetism acts.
• The Wavelength is the distance from one crest to another, or from one trough to another of a wave.
• Crest is the highest point of the wave
• Trough is the lowest point of the wave.
• The family of EM waves is referred to as the Electromagnetic Spectrum.
• Electromagnetic Spectrum is a term to describe the entire range of light that exists from radio waves to gamma rays. It is separated into many wave groups based on the generation mechanism, particular uses and effects, and a range of frequencies or wavelengths.
• EM waves travel in free space with a speed of 3.0 x 10^8 m/s
• EM waves exhibit diffraction and interference phenomena
• EM waves follow the rules of reflection and refraction
• EM waves can be polarized
• ⋋ is for wavelength
• F is for frequency in the triangle method
• c is for the speed in the triangle method
• ⋋ = c/f
• f = c/⋋
• c = ⋋f
• Radio waves are generated through the oscillation in electric circuits. Includes AM, FM, and some aviation broadcasting