Wave Characteristics and properties Wave A disturbance that

Wave Characteristics and properties

Wave • A disturbance that moves energy through matter or space.

Medium • The matter though which waves travel. • This only applies to mechanical waves.

Types of Waves

Mechanical waves • Waves that require a medium through which to travel. • Examples: Sound waves, surface waves and seismic waves (earth quakes)

Cool fact… • Surface waves are waves that travel along a surface like ocean waves. The particles of the medium (water) move in a circle.

Electromagnetic waves • A disturbance in the electromagnetic field that does not require a medium to travel. Travels through a vacuum (empty space). • Example: All waves in the electromagnetic spectrum (light).

Cool fact… • Space contains no matter so sound can not travel through it!

Transverse waves • Waves that cause the particles of the medium to vibrate perpendicularly to the direction the wave travels. • Example surface waves (water is medium). • Electromagnetic waves are transverse waves even though they do not require a medium to travel.

Longitudinal waves • A wave that causes the particles of the medium to vibrate parallel to the direction of the wave. • Examples: Sound and seismic waves

Parts of Waves

Crest • The highest point of a wave

Trough • The lowest point of a wave.

Wavelength • The distance from one point on a wave to the same point on the next wave.

Compression • The part of a longitudinal wave where the particles are close together.

Rarefaction • The part of a longitudinal wave where the particles are far apart.

Amplitude • The distance the particles of the wave are moved from the resting point. • The more energy a wave has the greater its amplitude.

Properties of Waves

Frequency • Measures the rate of the vibrations • The number of vibrations (waves) that happen in 1 second. • One vibration is one wavelength

Period • The time required for one full wavelength to pass a certain point.

Reflection • The bouncing back of a wave after it hits a barrier.

Absorption • The disappearance of a wave into a medium. • When a wave is absorbed, the energy of the wave is transformed into a different type of energy, usually heat.

Transmission • When a wave passes through a medium. • For example being able to hear people in the hall even when the door is closed. Sound waves are transmitted through the door.