The study of underwater sound propagation modelling is crucial for advancing the understanding of acoustic behaviour in complex marine environments. Researchers use an array of numerical ...

So far we have only considered sound in isolation and we have seen that sound has velocity, frequency, wavelength and reduces in intensity in proportion to the square of the distance from the source.

Two physicists in China have shown that it should be possible to observe negative refraction with sound waves. Xiangdong Zhang of Beijing Normal University and Zhengyou Liu of Wuhan University have ...

Phononic crystals are novel materials that offer exceptional control over phonons, sound and other mechanical waves. Taras Gorishnyy, Martin Maldovan, Chaitanya Ullal and Edwin Thomas report on a ...

THE principal object of this paper is to show that sound, instead of proceeding along the ground, is lifted or refracted upwards by the atmosphere in direct proportion to the upward diminution of the ...