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General Wave Properties. What is a wave?. A wave is a transfer of energy from one point to another via a traveling disturbance A wave is characterized by its wavelength, frequency, and amplitude. Transverse . Waves that travel perpendicular to the direction of motion
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What is a wave? A wave is a transfer of energy from one point to another via a traveling disturbance A wave is characterized by its wavelength, frequency, and amplitude
Transverse • Waves that travel perpendicular to the direction of motion • Examples: Light, -p wavesfor earthquakes, Ocean waves
Longitudinal • Waves that travel parallel to the direction of motion • Made up of compressions and rarefactions in the medium that they are traveling in • Examples: sound waves and s waves for earthquakes
Wavelength (λ) • Distance from successive crest to crest or trough to trough • Measured in meters
Frequency • Number of crests passing by per second • Measured in Hertz (Hz) defined to be one cycle per sec • Equal to the inverse of the amount of time it takes one wavelength to pass by
Amplitude • Maximum displacement of the wave • The amplitude will have different units depending on the type of wave • In a sketch of the wave, it is the distance from the middle of the wave to the peak
Electromagnetic Waves • Waves of energy emitted from any accelerating charges • Any object that is above absolute zero emits electromagnetic waves
Polarization Electric and Magnetic Field which make up wave have preferred direction Can be horizontal, vertical, circular, or elliptical Most radio emission is unpolarized
y Electric Field Electromagnetic Wave Magnetic Field x y Vertical Polarization Horizontal Polarization y E x z x E z Polarization Electric Field Electromagnetic Wave Magnetic Field