| Definitions: | Crest or Peak - The highest part of the disturbance on a wave |
| Trough - The lowest part of the disturbance on a wave | |
| Amplitude -The "height" of the wave, or in other words, a measure of the energy in the wave | |
| Wavelength - The length of one wave. This is measured by taking the distance from one point on a wave to the same point on the next wave. For example, the wavelength can be measured by taking the distance from one wave crest to the next. | |
| Frequency - The number of waves that occur every time period. You find the frequency of a wave by counting how many wave crests pass a fixed point in a certain interval of time. Frequency is usually measured in cycles per second, also known as hertz (Hz) |
The frequency, wavelength, and velocity are all related to each other.
velocity = frequency x wavelength
This means that frequency and wavelength are inversely proportional to each other. If the frequency increases wavelength will decrease. Why is this so? The reason is that velocity of a wave will not change unless the medium is changed. All sound waves will move the same speed in air (as long as the air stays the same temperature) This is why when you listen to music at a concert you hear the tuba at the same moment you hear the violin when they produce a sound at the same moment. If both waves have the same speed this means that the tuba's low frequency wave must have a long wavelength, and the violin's high frequency wave must have a short wavelength. Look below to see an example of this.
How do these different characteristics relate to sound waves? Click Here to find out.