Ryan Dittmer
MECHANICAL VS. ELECTROMAGNETIC WAVES
MECHANICAL
A mechanical wave requires an initial energy input to be created. Once this initial energy is added, the wave will travel through the medium until all the energy has been transferred. There are 4 types of mechanical waves. Transverse waves are waves that cause the medium to vibrate at a 90-degree angle to the direction of the wave. Two parts of the wave are the crest and the trough. The crest is the highest point of the wave and the trough is the lowest. The wavelength is the distance from crest to crest or from trough to trough. The next type is longitudinal waves. A longitudinal wave is much like a Slinky. When the particles the wave is traveling through are close together, it is called compression. When the particles it is traveling through are spread apart, it is called rarefaction. Another type of heat wave is an abdominal wave. This type of wave is the wave that twists along a given medium. An example would be: if a force twists a coil on one end, and released, the "twist" will travel completely through the wave and end up on the other side. The final type of wave is a surface wave. This type of wave travels along a surface that is between two media. An example of a surface wave would be waves in a pool, or in an ocean. Mechanical waves are a wave that requires a medium through which to travel.
long._wave.jpg
Transverse-Wave.gif
1.)
Which of the following in NOT a mechanical wave?

a. transverse b. longitudinal c. compression d. abdominal
2.) What is the tip of the wave called?
3.) What is the length between the waves called?

ELECTROMAGNETIC
Electromagnetic waves were first discovered by James Clerk Maxwell and then confirmed by Heinrich Hertz. Maxwell created a wave form of the electric and magnetic equations, revealing the wave-like nature of electric and magnetic fields. Because the speed of EM waves predicted by the wave equation coincided with the measured speed of light, Maxwell concluded that light itself is an EM wave. The physics of electromagnetic radiation is electrodynamics. Electromagnetism is the physical phenomenon associated with the theory of electrodynamics. Electric and magnetic fields obey the properties of superposition so that a field due to any particular particle or time-varying electric or magnetic field will contribute to the fields present in the same space due to other causes: as they are vector fields, all magnetic and electric field vectors add together according to vector addition. For instance, a travelling EM wave incident on an atomic structure induces oscillation in the atoms of that structure, thereby causing them to emit their own EM waves, emissions which alter the impinging wave through interference. These properties cause various phenomena including refraction and diffraction.

1.) Who first postulated Electromagnetic waves?
2.)What theory is electromagnetism associated with?


electro_wave.gifelectromagnetic-spectrum.jpg