What are Properties of Waves? | Definition, Types, Formula & Examples

What are Properties of Waves?

Scientists use many properties to describe waves. These include amplitude, frequency, period, wavelength, speed, and phase. Each of these attributes has been provided below with more details.

Graphing a Wave

When we plot a wave or look at a wave on a chart, we are plotting the wave as a snapshot in time. The vertical axis is the amplitude of the wave while the horizontal axis can be distance or time.

In this image you can see that the highest point on the wave chart is called the top and the lowest point is called the bottom. The line passing through the center of the wave is the resting position in the middle if no wave is transmitted.

We can determine some properties of waves from the graph.

Amplitude

The amplitude of a wave is a measure of the displacement of a wave from its resting position. Amplitude is usually calculated by looking at the histogram of the wave and measuring the height of the wave from the resting position.

Amplitude is a measure of the strength or intensity of a wave. For example, when looking at sound waves, amplitude measures the intensity of the sound. The energy of the wave also changes proportionally to the amplitude of the wave.

Wavelength

The wavelength of a wave is the distance between two corresponding points on successive periods of oscillation. This value can be measured between two wave crests or two wave troughs. Wavelength is often represented in physics by the Greek letter lambda (λ).

Frequency and Period

The frequency of a wave is the number of cycles per second of the wave. Frequency is measured in Hertz or cycles per second. Frequency is usually indicated with a lowercase “f”.

The wave period is the time interval between wave crests. Duration is measured in time units such as seconds. The time period is usually indicated with a capital “T”.

Period and frequency are closely related. Period equals 1 on frequency and frequency equals 1 on cycle. They are inverses of each other as shown in the following formulas.

period = 1/frequency
or
T = 1/f

frequency = 1/period
or
f = 1/T

Speed or Velocity of a Wave

Another important property of waves is the speed of propagation. This is the travel speed of the wave turbulence. The speed of a mechanical wave depends on the medium through which the wave travels. For example, sound will travel at different speeds in water than it does in air.

The speed of a wave is usually indicated by the letter “v”. Velocity can be calculated by multiplying frequency by wavelength.

velocity = frequency * wavelength
or
v = f * λ