Properties of Waves

Vocabulary flashcards covering wave definitions, characteristics, equations, wave types, homework comparisons, and diagrammatic properties from Chapter 14 lecture notes.

Wave

A progressive disturbance which transfers energy from one point to another without transferring matter.

Ripple tank

A shallow water tank used to demonstrate how waves behave.

Ripple

A small uniform wave formed on the surface of water by a vibrating bar moving up and down.

Wavelength ($\lambda$)

The distance covered by a wave to complete one oscillation/revolution, or the distance between adjacent crests or troughs.

Amplitude

The maximum vertical displacement of a wave from its equilibrium position.

Crest

The highest point or peak of a wave.

Trough

The lowest point of a wave.

Time period ($T$)

The time taken by a wave to form one oscillation or revolution.

Frequency ($f$)

The number of oscillations formed by a wave per unit time taken, calculated as $\text{frequency} = \frac{\text{number of oscillations}}{\text{time taken}}$ or as the reciprocal of the time period, $\text{frequency} = \frac{1}{T}$.

Hertz ($\text{Hz}$)

The SI unit of frequency, equivalent to $\text{s}^{-1}$.

Wave speed ($v$)

The rate at which the crest of a wave travels in a medium, or the speed of a wave in a medium.

Transverse wave

A type of mechanical wave where particles move perpendicular ($90^\circ$) to the direction of propagation of the wave, such as all electromagnetic waves (X-rays, radio waves, gamma rays).

Longitudinal wave

A type of mechanical wave where particles move parallel to the direction of propagation of the wave.

Compression

A region in a longitudinal wave where particles are closer together, characterized by high wave frequency, high pressure, maximum density, and corresponding to a crest in a transverse wave.

Rarefaction

A region in a longitudinal wave where particles are further apart, characterized by low wave frequency, low pressure, minimum density, and corresponding to a trough in a transverse wave.

P-waves

Longitudinal waves that travel faster, create sound, move parallel to the wave's direction, and travel through solids, liquids, and gases.

S-waves

Transverse waves that travel slower, create ripples on water, move perpendicular to the wave's direction, and travel through solids only.

Wave speed equation

The relationship between frequency, speed, and wavelength, given by $f = \frac{v}{\lambda}$ or $v = f \times \lambda$.

Diffraction

The spreading of waves after passing through a gap or past an edge, which is maximum when the size of the gap is equal to the wavelength.

Wave behavior when changing medium

When a wave moves from a less dense medium (air) to a more dense medium (glass), its wavelength and speed decrease, while its frequency remains unchanged because it is not affected by the change in the nature of the medium.

Wave parameters diagram

A diagram showing the amplitude (vertical displacement from equilibrium position), wavelength (distance between adjacent crests or troughs), crest/peak, and trough of a wave.

Transverse wave motion diagram

A diagram illustrating particles moving at $90^\circ$ (perpendicular) to the direction of wave propagation.

Longitudinal wave compression and rarefaction diagram

A diagram depicting the structure of a longitudinal wave, showing alternating regions of compression (particles closer) and rarefaction (particles further apart).

Refraction from air to glass diagram

A diagram demonstrating how a wave transitions from air to glass, changing from a bigger wavelength in air to a smaller wavelength in glass.