Sound is caused by vibrations of an object. When an object vibrates, it creates pressure waves in the surrounding medium—such as air, water, or solids—causing particles in that medium to vibrate as well. These vibrations propagate through the medium as sound waves, which are longitudinal waves consisting of alternating compressions (high pressure) and rarefactions (low pressure) of the particles

. As the vibrating object moves, it disturbs nearby particles, which then transfer the vibrational energy to adjacent particles in a chain reaction, spreading the sound wave outward. The particles themselves do not travel with the wave; instead, they oscillate around their original positions, passing energy along

. In summary, sound is produced by:

• An object vibrating, which disturbs the particles of a medium around it.
• The vibrational energy creating pressure waves (sound waves) that travel through the medium.
• These waves reaching a receiver (like the human ear), where they are perceived as sound

Sound cannot travel through a vacuum because there are no particles to transmit the vibrations

. The speed and behavior of sound depend on the properties of the medium, such as density, pressure, temperature, and viscosity