Sound and Noise
1934; Nature Portfolio; Volume: 134; Issue: 3398 Linguagem: Inglês
10.1038/134929c0
ISSN1476-4687
Tópico(s)Acoustic Wave Phenomena Research
ResumoA RESEARCH and Development Lecture on "Sound and Noise" was given at the Royal Institution on December 12, under the auspices of the Institution and the British Science Guild, by Dr. G. W. C. Kaye, Superintendent of the Physics Department at the National Physical Laboratory. Mr. Hore Belisha, the Minister of Transport, was in the chair. Man has developed very many and ingenious ways of making sounds and noises. In some everyday events the noise is only a small by-product; for example, only about a thousandth part of the energy of a dropped weight or of a hand-clap appears in the form of noise*. This figure was increased to a few per cent in the case of motor horns and loud speakers, and even up to 30 per cent or more for the loud speakers used for talking pictures. By comparison with many sounds,. the human voice is very weak, and even during shouting the output was only about 0-001 watt. Suitably equipped, an orchestra of 75 has a normal acoustic output of about 0-5 watt, which in strident passages may be increased 100-foldquite enough, if it could be so applied, to light an average electric lamp.
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