It is possible to convert a sound wave into an electrical signal. This allows you to study the waveform using an oscilloscope.
Transverse waves are actually longitudinal waves but oscilloscopes display them as transverse waves. Let’s look at a basic wave diagram and wave properties:
Amplitude – The distance between the midpoint and the peak of the wave, or the midpoint and the trough of the wave. A wave’s amplitude indicates how loud the sound is. The greater the amplitude, the louder the sound is.
Frequency – The number of complete waves that go past a given point per second. A wave’s frequency indicates the sound’s pitch. The higher the frequency, the higher the pitch. Frequency is measured in hertz (Hz).
Wavelength – The distance between two peaks, which are next to each other or any two identical points which are next to each other. In the basic wave diagram above, the wavelength is measured at the mid point, not the peak. Frequency and wavelength are linked, having a negative relationship. As the shorter the wavelength is, the higher the frequency will be.
We hear sound using our ears, as the sound makes our eardrum vibrate. Microphones contain a diaphragm, which works in a similar way to our eardrums. When sound vibrates in the air, it causes the diaphragm to vibrate, which is changed into electrical impulses.
Humans can hear a wide range of frequencies but we definitely can’t hear everything.
The range of frequencies humans can usually hear is between 20 Hz and 20,000 Hz (20kHz).
|Species||Hearing range (Hz)|
|Bats||20 – 120,000|
|Dogs||67 – 45,000|
|Elephants||16 – 12,000|
There are animals which can hear within the ultrasound region (more than 20,000 Hz), for example, bats.