Sound Waves Waves are disturbances that travel through a space while changing its matter. A sound wave is what allows us to hear sounds. It is created by vibrations, which are made by the movement of matter. Sound waves must travel through a solid, a liquid, or a gas. The more tight the particles, the faster the wave will travel. This would mean that a sound wave travels fastest through solids and slowest through gases.

The speed that it travels through a liquid would come somewhere in between the two because a liquid s particles are farther apart than solids, but closer than gases. When objects vibrate, their energy moves the matter around it and this is what our ears hear as a sound wave. Intensity is the rate at which sound energy enters the ear. Usually a sound with high intensity makes a loud sound. The intensity and volume of a sound wave decreases as the distance gets farther. As the ripples of a sound wave spread, they get larger and slightly fainter.

Intensity can be measured in a unit called decibels, which were named after Alexander Graham Bell, inventor of the telephone. When a sound wave enters your ear, it causes the eardrum to vibrate and those vibrations go past tiny bones to the inner ear. In the inner ear there are fluids and hair-like nerve endings which send messages to the brain to interpret the sound. Any levels of intensity over 90 decibels can permanently damage hearing. High levels of intensity can damage the hair-like nerve endings within the ear. The frequency of a sound wave is how fast the source of the sound is vibrating.

Frequency is measured in hertz. The average male voice is about 120 hertz while the average female speaking voice is about 250 hertz. The pitch is what the ear perceives of the frequency. It is usually referred to as how high or low a sound is.

It has no means of exact measurement. Sound waves are quite complex. There are so many aspects to the such as their intensity, frequency, and pitch. It is wonder that something so natural to human beings, such as sound, can be so technical yet no real effort is called for by us.

It s been programmed into our heads and ears since birth. Without sound waves, the world would be a very quiet place.