Wave definitions
The various parts of a wave are described below:
Wavelength
The distance from a point to another point where the wave begins to repeat itself. This could be the distance from The topmost point of a wave. to peak or The bottommost point of a wave. to trough. Wavelength is measured in metres (\(m\)) and has the symbol \(\lambda\).
Frequency
This is the number of waves produced in 1 second by the source producing the wave. The number of waves produced each second. The unit of frequency is hertz (Hz). is measured in The unit of frequency, symbol 'Hz'. 1 Hz is 1 wave or cycle per second. \((Hz)\) and has the symbol \(f\).
Amplitude
The The maximum height of a wave from the middle of the wave to its peak or trough. of a wave is half the distance from peak to trough. It can also be thought of as the height of the wave from the rest position (rest position = in the middle when the wave is not moving up or down). Amplitude is measured in metres \(m\). Amplitude is the letter \(a\) in the diagram below.
Wave speed
Wave speed is a measure of how quickly the wave travels from its source. Its value is the same as the distance covered by a wave in one second. Speed is measured in metres per second \(m\,s^{-1}\) and has the symbol \(v\).
Period
The The time taken to produce a single wave. Measured in seconds, eg the period of the wave is 0.5s. of a wave is the time taken for one complete wave to be produced. It is also the time taken for one whole wave to pass a point. Period is measured in seconds \((s)\) and has the symbol \(T\).
There is an important relationship between frequency \((f)\) and period \((T)\).
\(Period=\frac{1}{frequency}\)
\(T=\frac{1}{f}\)
Making the frequency the subject of the equation gives the formula:
\(f=\frac{1}{T}\)
In both equations: frequency is measured in Hertz \((Hz)\) and period in seconds \((s)\).
If there is a larger number of waves, \(n\), and the time for those waves to pass a point, \(t\), then the frequency can be found using the formula:
\(f=\frac{n}{t}\)
