The wavelength of the sound wave is 3 cm and the speed of sound is 340 ms-1. Using the formula speed = wavelength x frequency, the frequency is calculated to be 1133.33 Hz. This frequency is audible to humans because our hearing range is between 20 Hz and 20,000 Hz. Sound is a mechanical wave that requires a medium to travel through. As the vibrating object moves forward, it compresses the air in front of it, creating a region of high pressure called a compression. As it moves back, it creates a region of low pressure called a rarefaction. The faster the vibration, the higher the pitch since there are more compressions and rarefactions passing a fixed point