WAVES

What is a wave? Any disturbance that transmits energy through matter or space.

What is a medium? A substance through which a wave can travel. A medium can be a solid, liquid, or gas. Sound waves and ocean waves require a medium (these are mechanical waves)

Waves that don’t need a medium Visible light, microwaves, tv and radio waves are electromagnetic waves. They CAN travel through substances but move faster through empty space.

Types of Waves Transverse waves: particles move perpendicular to the direction the wave is traveling. (ex. Electromagnetic waves) crest trough

Longitudinal waves: the particles move back and forth along the path the wave travels. (sound waves) compressions rarefactions

Combination of Waves Surface waves are a combination of transverse and longitudinal.

Properties of Waves

Amplitude The maximum distance the wave vibrates from its rest position. (large amplitude= more energy)

Loudness of sound is related to amplitude. Amplitude of Sound Loudness of sound is related to amplitude.

Wavelength The distance between any two adjacent crests or compressions in a series of waves.

Frequency The number of waves produced in a certain amount of time. (the higher the frequency, the shorter the wavelength) Higher frequency means more energy Frequency is measured in Hertz (Hz) waves per second.

Frequency of Sound Frequency of sound is called pitch. This determines how high or low a sound is.

Wave Interactions

Reflection When a wave bounces back after striking a barrier. Reflected sound waves are called echoes.

Refraction The bending of light waves as they pass at an angle into a new medium.

Diffraction The bending of waves around a barrier or through an opening.

Interference Two or more waves overlapping.