Natural Science Forum / Physics / Acoustics / October 2006

Can anyone suggest octave band absorption coefficients for a solid
steel roof deck. It is a fluted Type B; 1-1/2" prifile depth.
Galvanized steel - 0.0358 in thick.  The entire deck is about 3000
square feet.  It will have 5" of polyiso insulation on top and and EPDM

I have a relative that has a house next to a neighbor who is running an
in-home daycare. Generally the children reside outdoors unsupervised and
scream for most hours of the day. The neighbor is directly adjacent to my
relative.

A week or two I was watching a TV program, CSI New York I Think, where
some thieves destroyed all the glass cases in a jewelry store using an
ultrasonic sine wave signal generator. I know that the right frequency
can break a wine glass and I've seen focused ultrasound set fire to

If you look at the standard acoustical parameters:
L1, L10, L90, Leq, Lmax etc
Clearly there is no basis for averaging the Lmax, whereas the Leq is a
continuous average level.

I have few 40kHz T and R  ultrasonic transduces, and don't have any
info about thier beam width,
can anyone let me know how to measure their beam width please?
Thanks in advance

I am currently trying to ensure that the noise from a clay pigeon
shooting range does not disturb neighbours.  The UK Institute of
Environmental Health have published a document that suggests how to
measure the noise from these shooting ranges, by combining the peak

What is Pressure on a solid (Physics)
Site for physics learners containing articles, links, sites etc.
http://www.studyandjobs.com/pressure-on-a-solid.html
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I have read about the neurophone which claims to produce auditory
perception through nerve stimulation. Something to do with electric
signals of certain frequencies being sensed as sound by the brain.
Science proves that temporal bone vibration can be used to cause