Final answer:
Sound is created by vibrations disturbing molecules, forming waves that can induce resonance and oscillations in matter. The ear detects these vibrations and sends signals to the brain, enabling the sense of hearing. Spectral fingerprints in sound waves can also allow identification of molecular vibrations.
Step-by-step explanation:
Sound is a physical phenomenon that originates from vibrations. These vibrations disturb molecules in a medium, typically the air, to create sound waves. When these waves reach our ears, they move the eardrum, transmitting signals to our brain which we interpret as sound. Hearing is thus one of our primary senses, which allows us to perceive these signals.
Sound can be produced by anything that causes a disturbance in the air, leading to a pulse that travels from the source. If the pulse is repetitive, it forms a sound wave, which can induce resonance effects and oscillations in the matter it passes through. This wave-based nature of sound is crucial for our perception of it, and explains why certain sounds can induce vibrations in other objects, a phenomenon known as sympathetic vibration or resonance.
Further, just as light has a spectrum, sound waves also have unique characteristics that can be identified through their wavelengths. This analogy extends to molecular vibrations, which, at longer wavelengths like radio and infrared, can leave spectral 'fingerprints'. These are used in various applications, one being the observation and study of interstellar matter.