Properties of Waves

Vocabulary and formulas covering the physical properties, movement, and types of mechanical and electromagnetic waves.

Waves

A disturbance that transfers energy from place to place.

Energy

The ability to do work.

Vibration

A repeated back-and-forth or up-and-down motion.

Medium

A substance composed of solid, liquid, or gas through which a wave can travel.

Mechanical waves

Waves that only travel through a medium, such as water, air, or a rope.

Electromagnetic waves

Waves that can travel through empty space, including X-rays, visible light, microwaves, radio, and UV - ultra violet.

Transverse Waves

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

Crest

The point in a transverse wave where the displacement of the medium is at a maximum.

Trough

The point in a transverse wave where the displacement of the medium is at a minimum.

Rest position

The position in a transverse wave where the medium shows no disturbance.

Amplitude (Transverse)

The vertical distance between a peak or a valley and the resting position.

Wavelength (Transverse)

The distance between two corresponding parts of a wave, such as crest to crest or trough to trough.

Longitudinal Waves

Waves where the medium moves parallel to the direction the waves are traveling, moving back-and-forth in the same direction.

Compression

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

Rarefaction

The part of a longitudinal wave where the particles are spread out.

Amplitude (Longitudinal)

A measure of how compressed or rarefied the medium becomes.

Wavelength (Longitudinal)

The distance from one compression to the next.

Frequency

The number of complete waves (wavelengths) that pass a given point in a certain amount of time, measured in units called hertz ($Hz$).

Hertz ($Hz$)

The unit of measurement for frequency, where $1\,\text{vibration per second} = 1\,\text{Hz}$.

Speed

How far a wave travels in a unit of time, calculated as distance divided by time, with the unit meters per second ($\text{m/s}$).

Speed Formula

$$\text{Speed} = \text{Wavelength} \times \text{Frequency}$$

Frequency Formula

$$\text{Frequency} = \frac{\text{Speed}}{\text{Wavelength}}$$

Wavelength Formula

$$\text{Wavelength} = \frac{\text{Speed}}{\text{Frequency}}$$