Unit wording switcharound...

[CiviTech]

Does anybody know why sometimes units are expressed in centi-Newton meters (cN/M) versus Newton centi-meters.

Richmont/Sturtevant does this (cN/M) and it is just driving me crazy, because in my head those two are different, however when you go to do conversions, thay are almost identical.

Perhaps I'm just going loony.

Thanks.

[WestCoastCal]

My guess? they never bothered to look at NIST SP 330 or 811.  This was a very good example, the proper unit symbol is N cm or N·cm.  The space between Newton and centimeter or half high centered dot (ALT-0183) indicates multiplication, whereas a "/" or a negative exponent indicates division, example:  Pressure = Force/Area.  So if they are in fact dividing their Newtons by their cm they are way the hell off!  Some of my personal favorites " for inch, S for second, lb/in^2 for psi. MG for milligram (or really old sig gens, kilo-mega cycles)
I really couldn't find a reference, to this situation Anyway, section 5.3.3, Formatting the value of a quantity of NIST SP 330 (2008) states in part The numerical value always precedes the unit,...so I guess you can infer that any multiplier/divider to the unit should be performed on the numeric portion of the statement.

[Mike]

Does anybody know why sometimes units are expressed in centi-Newton meters (cN/M) versus Newton centi-meters.

Richmont/Sturtevant does this (cN/M) and it is just driving me crazy, because in my head those two are different, however when you go to do conversions, thay are almost identical.

Perhaps I'm just going loony.

Thanks.

You are indeed going loony


There is no difference in centi Newton meters and Newton centi-meters.  they are identical through the cumulative property of multiplication.

Your "/" sign above is incorrect...it is not division.  you are multiplying the force times the length to get torque, not dividing it.

10 newtons applied at 1 centimeter is the same as 1 newton applied at 10 centimeters.  or 10 centi-newtons applied at 1 meter...or 1 centi-newton applied at 10 meters   

[Bryan]

I use the grunt/foot, that is to say 2 grunts on a 6" wrench = 1 grunt on a 12".  It's not very scientific but when your down to using a crescent wrench for a micrometer it seems good enough.