A wave is a vibratory disturbance through a material (medium) or space.Waves transfer energy without transferring mass.

No medium required.Travel at the speed of light .c = 3 x 108 m/sExamples: visible light, x-rays, infrared

rays

MECHANICHAL WAVES

Require a medium ex. Sound, water, waves in springs.

• Longitudinal wavesExamples - sound, seismic s-waves• Transverse wavesExamples: light, seismic p-waves, water

TRANSVERSE WAVES

Waves that move the medium at right angles to the direction in which the waves are traveling .

CREST AND TROUGH

Crest: A point on the wave where the displacement of the medium is at maximum.Trough: A point on the wave where the displacement of the medium is minimum.

LONGITUDINAL WAVES

Longitudinal waves have vibrations moving in the same direction that the wave is travelling in.

COMPRESSSION AND RAREFRACTION

Compression: A region in a longitudinal waves where the particles are closest together.Rarefraction: A region in a longitudinal wave where particles are farthest apart.

PROPERTIES OF WAVES

Amplitude Frequency Speed wavelength

AMPLITUDE

Maximum distance the particles of the medium carrying the wave move away from their rest positions.

Amplitude of a transverse wave is the maximum distance the medium moves up or down from its rest position.

Amplitude of a longitudinal wave is a measure of how compressed or rarefied the medium becomes.

WAVELENGTH

A wave travels a certain distance before it starts to repeat. The distance between two corresponding parts of a wave is its wavelength.

Transverse measure from crest to crest or trough to trough.

Longitudinal measure from one compression to the next.

The number of complete waves that

pass a given point in a certain amount of

time.

Frequency measured in hertz

SPEED, WAVE LENGTH & FREQUENCY

The speed, wavelength, and frequency of a wave are related to each other by a mathematical formula.

Speed = wavelength x frequency Frequency = speed/wavelength Wavelength = speed/frequency