The sound propagates in an elastic medium (solid, liquid or gas).

The speed of sound propagation depends on certain properties of the material in which it propagates: pressure, the heat, compressibility (density)..

Waves interact with different materials by being reflected, absorbed and transmitted. This occurs in both sound waves and light waves. Scientists and engineers have been able to develop technologies that use this idea to improve our lives. Bats and whales do the same thing as they listen to reflected sound waves to locate prey and avoid obstacles. Read the information below and explore the videos and links as you learn about this and look for examples of reflection, absorption and transmission.

Anything that vibrates can create a sound wave. Vibrating particles can cause other nearby particles to vibrate also, allowing the sound wave to move from place to place. Transmission of sound requires a medium, like gas, liquid or solid, which are all composed of particles.

Persistence of sound in an enclosed or semi-enclosed space after the sound source has been interrupted.