Just curious... the untis of the inverse of an Ohm are a Mho (cute). Is there an equivalent for the inverse of Farads and Henries? I realize that most of the time you're after the impedance broken into the resistance and reactance (units: ohms) or the admittance broken into conductance and susceptance (unit: mhos), but I figure there's a good chance someone named
---Joel Kolstad
Nothing physically, just an 'interim' unit if you want to talk about, say, parallel inductors or series capacitances.
Apparently I'll just stick with F^-1 and H^-1...
---Joel
But writing an upside-down Omega is so much fun!
Do you have anything that suggests Mho is actually deprecated rather than simpler synonymous with Siemens?
---Joel
No, it is called Siemens. Mho does not exist in the modern world.
Fair enough...
It is amsuing that the English have switched to SI whereas the US hasn't yet! ;-)
True, but statistically speaking there are going to be more mistakes when engineers have to work in multiple systems. There are good examples out there of very large dollar systems such as satellites failing due to this problem.
Thanks Joe!
The SI system is the international scientific and technical standard in the modern world. There is no Mho in that system.
We should avoid all older or regional units and use the SI system to simplify understanding and education in a global perspective.
An Engineer worth his salt should be able to work in any system presented.
Hi,
The reciprocal of 'Capacitance' is 'Elastance' which comes from the similarity to the spring constant. It is measured in 'Darafs' would you believe. The reciprocal of 'Inductance' is sometimes given as 'Reluctance' but you have to do a dimensional hand-stand to accept it. Cheers - Joe
Not that I know of. However, the 1/Ohm, or what was called a "mho" is now officially called a "Siemen". It is possible that someone, somewhere uses a Daraf or a Yrneh but why? Susceptance (-1/2*pi*f*L or 2*pi*f*C) is in Siemens. (mhos If you don't want to change habits)
Are your texts all out of date? The Siemen is used in US engineering texts and literature.
I meant in general... when you go to the store to buy furniture in the U.S., the dimensions are in inches/feet/etc.
On the technical side, if you look at magnetics manufacturers, many of them still use slightly non-SI units... it's apparently a slow industry to change. (I was at a seminar once where the speaker mentioned, "You have to realize, they're basically just selling you a bunch of processed dirt..." :-) )
---Joel
hasn't
U.S.,
them
to
Sure and I calculate my gas consumption in miles per gallon- translating from liters/100km. even though I have been using metric units for 50 years and SI since it came into official play. My tape measure still is in inches and feet and I am in an officially SI country next door north from you. However, dealing with Gauss instead of Tesla is not a problem- I just convert and carry on. Lines/sq. inch -oops-what is the bugger factor? At least we don't play around with abvolts, abamperes or statvolts and statamperes. :)
another way to conform our government to the rest of the world
What has the government to do with it. It makes good sense. Good sense and government rarely go together.
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