IN GREEK mythology, Echo was a mountain nymph who lost her voice and was condemned to repeat only the words of others. Now science is poised to silence the sprite completely. A group of physicists, ...

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.

THE principle that a regularly stratified medium selectively reflects a monochromatic beam of radiation incident on it at the appropriate angle is well known and forms the basis for the X-ray analysis ...

No, I am not sitting in my home theater at 6:00 a.m., ruminating about how the pattern on the wall from the lighting sconce looks different from the back row. This article is about sound reflections.