Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, Russia. One of the problems is still causing a number of questions; it is the calculation of the coefficients of reflection ...

Department of Industrial Engineering, University of Bologna, Bologna, Italy. Noise barriers can be very different for shape and materials, and every day new ones are appearing on the market. It is ...

Waves close wavesVibrations that transfer energy from place to place without the transference of matter. , including sound and light, can be reflected at the boundary between two different materials.

Whether a sound wave is reflected, refracted, or absorbed depends on the densities of the materials either side of the boundary. If the densities are very different then reflection is more likely.