[USMA:30439] Re: Fw: your "Metric Meddlers" column in the Telegraph

[MightyChimp]

The FFU-ists keep insisting that metric units too have changed, even though they back off when proof is demanded.  Sometimes though they will claim that each time the definition has changed, so has the unit itself.    But as I also said, many confuse (I think deliberately) precision and resolution.  They assume, for example if a bridge clearance is stated as 4.5 m high and the FFU equivalent is 14 feet 9 inches, the FFU is more precise because the resolution is stated to the nearest inch (25 mm) whereas the metric value is to the nearest 100 mm.  However, by their reasoning  if I state the distance as 4 feet 9 and 21/128-ths inches I'm even more precise.    The fact is, this is not true.  If the measurement or design was only accurate to the nearest 0.1 m then that is as accurate as any number can be.  Showing more digits and more resolution does not increase accuracy, it just makes numbers more complex then need be.   I recently posted a web page from a guy who claimed construction in FFU was better because the centimetre was too small and the metre to large.  Yet, when these comments are made, never is a construction worker from a metric country ever consulted and asked which system is easier.  Familiarity can be confused with ease.  One can learn and become familiar with metric as easy as one learned FFU, but few give metric a chance to make a true comparison  So until FFU is totally dead, we will have to put up with the resistance, which will get heated as more and more of the ignoranti are backed further and further into a corner.   Euric ----- Original Message ----- From: David King To: U.S. Metric Association Sent: Thursday, 2004-07-15 18:34 Subject: [USMA:30429] Re: Fw: your "Metric Meddlers" column in the Telegraph The inch is precisely defined as 25.4 mm, however, this can never be more precise than metric. As MightyChimp wrote, FFUs are today defined more by their metric equivalents. For centuries the imperial measurements have changed over time, between places and sometimes the names changed, where is precision in that? It is so unprecise that we need the metric system, as that has a precision that no other system ever had. The length of a man's foot (e.g. a king or emperor) is not precise for creating a unit length, after all, his feet may shrink with age, and when he's dead then whose foot does society then use as the measuring unit? David MightyChimp wrote:   Which "old fashioned" units are more precise then metric units?  This statement in itself is in error.  A unit can not be precise, only the definition of it can be.  SI units are all precisely defined by a physical referance.  FFU units are defined from SI and their precision depends on how accurate the conversion factor is.    Also the precision of the measuring device plays a role in how precise a measurement is.