March 21, 2004

The Return of the Standard Hair

Way back in 2001 when the original confusion about the relation of a nanometer to the width of a human hair originally surfaced, reader David Neiman, was kind enough to send us a histogram of hair widths from his own locks (average fibre diameter 72.1 microns with a standard deviation of 24 microns and a coefficient of variation of 33.3% for the statistically minded). Of course hair colour and the part of the body the sample was taken from also influence the diameter.

Confusion still rages with a nanometer being 100,000 times smaller than a human hair (making a hair 100 microns in diameter) to 1,000 times smaller (1 micron).

Three years later we still await a scientifically valid analogy. May we suggest a slightly tighter definition, that a nanometer is one hundred million times smaller than a large potato (which would have to vary between 1cm and a one meter in diameter to provide the same statistical variation as the hair analogy). Perhaps not.

Posted by Cientifica at March 21, 2004 07:40 PM | TrackBack

Very easy analogy: Assuming you take an imaginary rubberband of approximately one yard length (a little less than a meter) and you stretch it from Los Angeles all the way to New York (ca. 4000km), then one nanometer would have been stretched to 4mm (or 0.16 inches). This should give the average person an idea of the scales involved.

Posted by: Michael Mehrle at March 25, 2004 05:17 PM

My personal favorite nanometer standard: the distance your fingernails grow in one second. This varies with age, gender, and which nail, but seems to be accurate within 25-50% from what I can determine. Certainly better than the human hair standard!


Posted by: Chris Phoenix, CRN at March 25, 2004 07:41 PM
Post a comment

Remember personal info?