waves vocab

Wave

A disturbance in a medium.

Medium

A substance or material that carries the wave.

Amplitude

The maximum amount of displacement of a particle on the medium from its rest position.

Wavelength

The length of one complete wave cycle.

Crest

The point on the medium that exhibits the maximum amount of positive or upward displacement from the rest position.

Trough

The point on the medium that exhibits the maximum amount of negative or downward displacement from the rest position.

Period

The time for a particle on a medium to make one complete vibrational cycle.

Frequency

How often the particles of a medium vibrate per second when a wave passes through the medium.

Hertz

Unit for frequency (1 Hz is equivalent to 1 cycle/second).

Transverse Wave

A wave in which the particles of the medium are displaced in a direction perpendicular to the direction of energy transport.

Longitudinal Wave

A wave in which the particles of the medium are displaced in a direction parallel to the direction of energy transport.

Compression

A point on a medium through which a longitudinal wave is traveling that has the maximum density.

Rarefaction

A point on a medium through which a longitudinal wave is traveling that has the minimum density.

Superposition

When two waves interfere, the resulting displacement of the medium is the algebraic sum of the displacements of the individual waves.

Traveling Wave

Wave pattern that is seen traveling through a medium.

Standing Wave

Wave pattern that appears to be standing still, caused by superposition of two waves of the same frequency and wavelength.

Node

Point of no displacement on a standing wave.

Antinode

Point of maximum displacement on a standing wave.

Harmonic Frequencies

Frequencies that result in standing wave patterns.

Resonance

When one object vibrating at the same natural frequency of a second object forces that second object into vibrational motion.

Constructive Interference

Type of interference that occurs where two interfering waves have a displacement in the same direction.

Destructive Interference

Type of interference that occurs where two interfering waves have a displacement in the opposite direction.

Doppler Effect

The effect produced by a moving source of waves in which an apparent upward shift in frequency is observed when the observer and the source are approaching, and an apparent downward shift when receding.