# To construct a resistance of X ohms...

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Let M be a positive integer , M=< 100 . Using only M perfect one ohm

resistors, construct a resistance of X ohms , were X approximate ,, gamma"

[ gamma :=Euler's constant= = lim_{n-->infty}(1/1 + 1/2 + 1/3 +...+ 1/n - ln(n) ) =

= 0.57721566490153286060651209008....]

with at least seven decimals (only series-parallel circuits are allowed).

Which is the minimum of M ?

See: [1] Problem E2459 proposed by A.A.Mullin in Amer.Math.Monthly (1974) [2] Problem 393 from Matematicki Vesnik 13(28)(1976),solution in 15(1978).

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First, show me how to construct a *perfect* one ohm resistor....

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Of course, it's assumed "theoretically possible" ! Thanks,proposer

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:)

long explanation on the care and feeding of standard resistors

pic of a early standard resistor

check out the quantum hall effect resistance standard in Japan
like a brain transplant device to me :)

remember what they say around Christmastime.... there is no place like 'ohm

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the ohm is the resistance of a column of mercury, 106.3 cm long and of 1 sq. mm cross section at 0 degree C. (Text Book of Electricity and Magnetism, G.R. Noakes, Macmillan, 1956)

:)

there you have it, can't be any more perfect than the definition.

William

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Thanks, now all you have to do is tell me how to make a column of mercury that is exactly 106.3 cm long and 1 sq mm cross section... ;)

BTW, to answer you question in another thread, I am a bus driver*.

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erm, erm, erm

:)

Eureka, oh no sorry it's me who stinks!!

erm, erm, erm.

Well maybe start with making a glass cylinder with a 1mm sq area whole through it's middle.

And then fill it with mercury (after stopping one end of course).

Simple!! ;)

how restrictive!!

we have no rights these days, things such as rights have become a pseudo fact.

I have this image in mind of your bus having a pc installed which automates it. Sue sits there with her feet up reading the news paper and her sensors and servos do the rest... proper little Queen of Sheba. Ah that's the life... No wonder she's always smiling. Just when the law comes into it, makes her stern faced.

:(

Poor Sue!!

William

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is some states here its aginst the law to NOT give first aid if you are qualified and able to do so. (im not sure how often these are actully enforced)

i admire your courage of conviction and wonder what other factors were involved in you decision.

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Getting very OT, I'm afraid. But it is related to first aid in the workplace - which may affect quite a few electrical engineers, in theory only (hopefully).

Well, the rule was introduced after they had tried (and failed) to discipline me for leaving the bus to give emergency aid earlier in the year - and my refusal to agree not to do so in the future. We are/were trained to the "Appointed Person" level (about the lowest level of first aid certification there is) and are supposed to render first aid until someone better-trained is available.

However, they said that was only "in the workplace" (i.e. the bus) and only applied to giving aid to employees and fare-paying passengers. Presumably, if someone did have a heart attack on the bus, my first check should have been of his ticket ;)

The engineering work-place analogy seems to be, an "Appointed Person" could and should help a fellow employee at work who, say, electrocuted himself. But he shouldn't step out of the building onto the street to give the help to a pedestrian walking by, electrocuted by a faulty street light. Your company could become liable, apparently.

I don't know what the position is "across the pond" - I get the impression that your society is even more litigatious and wonder what your rules for rendering first aid in or near the workplace are..

Here, in the UK, an increasing number of activities are being curtailed because of the threat of litigation, including Village Fetes, "conkers", selling home-made cakes by Women's Institute, selling second-hand electrical equipment from charity shops, etc. A Chartered Electrical Engineer is no longer "qualified" to safety-test a mains radio..

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We are not bound by such statutory duty here. We can however be held negligent if we do something incorrectly and we must continue to provide care, in some instances, if we initiate care.

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yep everybody wants to sue somebody it seems... and every one has heard about the hot chocolate at the drive-in case, however it is my understanding that many many silly lawsuits are rejected by level headed judges: "you bought a hot beverage, spilled on yourself, and now you want to sue someone? get out of my court and pay the court costs too!" its just that when the system works the way it should it isn't newsworthy so news coverage of the oddball cases make it seem like everything is out of proportion.

and likewise insurance costs are restricting activities like concerts, fireworks, and many other public events.

i was amazed to discover that the UK requires a license to have a TV set. can you tell me the justification behind such a law?

if an EE is not allowed to test electronics.... who is? a PHD? or is it only left handed descendants of Tesla?

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Which kind of bus Sue? Big? Small? Quick on takeoff?

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