What Is a Sound Wave?
Sound waves are vibrations that move the air around us. The waves travel towards your ear by vibrating the air near to where the sound was made which then vibrates the next bit of air and so on until the wave arrives at your ear. Sound waves travel in lots of different directions from where the sound first started. Your ear ‘catches’ the bit that comes in your direction. Once your ear has ‘caught’ the sound, it carries on vibrating inside your ear all the way to your ear drum. These vibrations are then turned into an electric message that your brain reads and tells you what sound you have heard.Â
What Is Pitch?Â
Pitch can be high or low. A high pitch sound is like chalk screeching on a blackboard and a low pitch sound is like the rumble of thunder. The pitch of a sound tells us how fast the sound vibrated when it was first made. A low note will have a slow vibration and a lower frequency. A high note will have a fast vibration and a higher frequency. You can make a string on an instrument have a higher pitch by shortening the string or making it tighter.Â
What Is Volume?Â
Volume is how loud a sound is, no matter the pitch of the note. It is measured in decibels (dB). Volume is the strength of the vibration the sound makes. A quiet sound has a gentle vibration and moves the air gently. A loud sound has lots of strength, moves the air with greater force and travels further. If we wanted to make the sound from a guitar string louder, but the same pitch, we would simply pluck it harder.