Final answer:
There are two types of sound waves: longitudinal waves, characterized by compressions and rarefactions, and transverse waves, which have oscillations perpendicular to the wave's direction. Longitudinal waves are common in fluids while transverse waves can occur in solids and on the strings of musical instruments. Sound waves have characteristics like frequency and amplitude, and humans hear frequencies between 20 Hz and 20,000 Hz.
Step-by-step explanation:
There are two kinds of sound waves, longitudinal waves and transverse waves. The former is a simple sound wave, characterized by a sinusoidal wave. Longitudinal sound waves consist of compressions and rarefactions, and this type of wave is typically found in fluids such as air and water, where the particles of the medium vibrate parallel to the direction of wave propagation. Transverse waves, on the other hand, consist of oscillations that are perpendicular to the direction of wave travel and are often observed on the strings of musical instruments or in electromagnetic waves like visible light.
Sound waves in solids can be both longitudinal and transverse since solids have the ability to support shear stress which allows transverse waves to travel through them. These waves have four main characteristics: frequency, wavelength, period, and amplitude. The frequency, heard as pitch, can vary greatly among different species, with humans able to hear frequencies between about 20 Hz and 20,000 Hz. More advanced concepts include the idea that sounds above the human hearing range are known as ultrasound.