Interesting facts about sound
November 12, 2009 | In: Science facts
For humans, hearing is normally limited to frequencies between about 12 Hz and 20,000 Hz (20 kHz).
Sound with frequencies of less than 20 Hz is known as infrasound. If a sound has a frequency that exceeds 22,000 Hz it is called ultrasound.
Sound is transmitted through gases, plasma, and liquids as longitudinal waves, also called compression waves.
The sound of a whale song can travel a distance of 800km.
In the air sound travels at the speed of about 335 metres(6100 feet) a second.Sound travels about 4 times as fast in water as it does in air.
Sound waves are invisible because the human eye can’t see pressure waves. But an oscilloscope can detect and show the shape of sound waves very accurately.
The accepted units for sound pressure are metric, Newton per one square meter (N/m2).
Scientists believe that the loudest sounds made by any animal are the whistles of the blue whale, which have been measured at up to 188 decibels — a million times more intense than a jet engine, which is only about 120-130 decibels! (Every 10 decibels represents a 10-fold increase in sound intensity.)
4 Responses to Interesting facts about sound
MarNie
March 11th, 2010 at 12:46 pm
A frequency of 19hz may be responsible for ghost sightings. This frequency is close to the resonant frequency of the eye and would therefore result in ghostly visual illusions in the listener
I didn’t make this up !!!!
Source: http://relentlessenergy.com/features/view/soundbites-the-noise-of-history
Ausley
April 17th, 2010 at 2:28 pm
thanks
alex
March 22nd, 2012 at 7:17 pm
this is very interesting to me it helped me to find out what i needed
drake
May 14th, 2012 at 8:55 am
MarNie…i dont beileve you