The ability to perceive sound is critical for the survival of most species on Earth, including humans. The ability to assess the environment through hearing evolved in a variety of ways in the animal kingdom, and high-functioning animals such as humans adapted the sense of sound as a means to communicate.Continue Reading
Sound is created when mechanical energy travels through an elastic medium, such as air. These waves of energy travel into the ear, where the brain interprets them as sound, alerting the listener to potential predators, environmental threats, food, water or peers. Hearing the sound of an approaching tiger, an impending waterfall or a potential meal increased the chances of early human survival. The development of language increased human reliance on hearing as humans learned to express more complex ideas through sound.
In modern times, hearing traffic or the din of a restaurant alerts people to the same dangers and attractions. Humans and animals began using vocal communication long before the development of language, alerting one another to threats, food and mates. The great apes, such as chimpanzees and gorillas, provide excellent examples of pre-language vocal communication. When observed in groups, they can be seen communicating with one another through a variety of sounds and gestures.Learn more about Optics & Waves
Pitch refers to the frequency of a sound, while loudness refers to the size or amplitude of the sound. Every sound has both a specific pitch and loudness.Full Answer >
It is unknown who discovered sound. It is known that discoveries regarding sound and how it travels were made as far back as 1500 when Leonardi Da Vinci discovered sound traveled in waves.Full Answer >
The human perception of sound intensity is known as the pitch of the sound. The pitch of the sound is created by the frequency of the sound waves that enter the ear. Human ears have the ability to hear sound frequencies between 20 hertz to 20,000 hertz.Full Answer >
An echo is the reflection of sound waves off distant objects, whereas flutter echoes bounce repeatedly off multiple surfaces. An example of an echo is when someone shouts into a well, or along canyon walls, and the sound of the human voice comes back to the person's ears. A flutter echo occurs in large buildings with parallel walls, such as gymnasiums, where sounds increase to create loud environments.Full Answer >