Peter T. Daniels ran out of electrical outlets; states rewiring entire house to be the only feasible solution.
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From: Skitt on 29 Mar 2010 12:40 Doctroid wrote: > Peter Moylan wrote: >> PaulJK wrote: >>> Doctroid wrote: >>>> "PaulJK" wrote: >>>>> Voltage and current are proportional to each other. >>>>> It is therefore sufficient to say that damage is proportional >>>>> to one of them. >>>> Only in materials and voltage/current ranges where Ohm's "law" is >>>> obeyed. And if damage is occurring, it probably isn't. >>> >>> Ohm's law is always obeyed in all aparatus made by humans. >>> >> Except when it isn't - which is most of the time. >> >> It's true that a great many resistors are nearly linear, i.e. they >> can be said to obey Ohm's law to a reasonable degree of accuracy, >> provided that you don't go beyond their design limits. >> >> It's equally true that some resistive devices are *deliberately* >> made to be nonlinear. A semiconductor diode, for example, would be >> totally useless if it obeyed Ohm's law. > > Besides which, the subject under discussion was not human-made > apparatus, but humans. > > And again, under conditions where the electric current is causing > tissue damage, Ohm's "law" doesn't really apply. Ohms law applies quite well. It is the encountered resistance that is changing as the skin (of much higher resistance than the mushy and moist innards) is damaged. -- Skitt (AmE) remembering his school days ...
From: Doctroid on 29 Mar 2010 12:58 In article <hoql5j$rn5$1(a)news.albasani.net>, "Skitt" <skitt99(a)comcast.net> wrote: > Doctroid wrote: > > Peter Moylan wrote: > >> PaulJK wrote: > >>> Doctroid wrote: > >>>> "PaulJK" wrote: > > >>>>> Voltage and current are proportional to each other. > >>>>> It is therefore sufficient to say that damage is proportional > >>>>> to one of them. > >>>> Only in materials and voltage/current ranges where Ohm's "law" is > >>>> obeyed. And if damage is occurring, it probably isn't. > >>> > >>> Ohm's law is always obeyed in all aparatus made by humans. > >>> > >> Except when it isn't - which is most of the time. > >> > >> It's true that a great many resistors are nearly linear, i.e. they > >> can be said to obey Ohm's law to a reasonable degree of accuracy, > >> provided that you don't go beyond their design limits. > >> > >> It's equally true that some resistive devices are *deliberately* > >> made to be nonlinear. A semiconductor diode, for example, would be > >> totally useless if it obeyed Ohm's law. > > > > Besides which, the subject under discussion was not human-made > > apparatus, but humans. > > > > And again, under conditions where the electric current is causing > > tissue damage, Ohm's "law" doesn't really apply. > > Ohms law applies quite well. It is the encountered resistance that is > changing as the skin (of much higher resistance than the mushy and moist > innards) is damaged. Your argument is circular. If you define "resistance" as the ratio of voltage to current, possibly varying with time, voltage, or current, then sure, Ohm's Law works; but then Ohm's Law becomes a tautology, trivially satisfied by everything and predicting nothing. The "law" is a useful law only in circumstances where voltage and current do not alter the electrical properties of the material; then it becomes an observation that current is proportional to voltage for all voltages and currents within some large range of applicability. That observation is not valid for the situation described here. -- Sig available on request. - Doctroid
From: Skitt on 29 Mar 2010 13:12 Doctroid wrote: > "Skitt" wrote: >> Doctroid wrote: >>> Peter Moylan wrote: >>>> PaulJK wrote: >>>>> Doctroid wrote: >>>>>> "PaulJK" wrote: >>>>>>> Voltage and current are proportional to each other. >>>>>>> It is therefore sufficient to say that damage is proportional >>>>>>> to one of them. >>>>>> Only in materials and voltage/current ranges where Ohm's "law" is >>>>>> obeyed. And if damage is occurring, it probably isn't. >>>>> >>>>> Ohm's law is always obeyed in all aparatus made by humans. >>>>> >>>> Except when it isn't - which is most of the time. >>>> >>>> It's true that a great many resistors are nearly linear, i.e. they >>>> can be said to obey Ohm's law to a reasonable degree of accuracy, >>>> provided that you don't go beyond their design limits. >>>> >>>> It's equally true that some resistive devices are *deliberately* >>>> made to be nonlinear. A semiconductor diode, for example, would be >>>> totally useless if it obeyed Ohm's law. >>> >>> Besides which, the subject under discussion was not human-made >>> apparatus, but humans. >>> >>> And again, under conditions where the electric current is causing >>> tissue damage, Ohm's "law" doesn't really apply. >> >> Ohms law applies quite well. It is the encountered resistance that >> is changing as the skin (of much higher resistance than the mushy >> and moist innards) is damaged. > > Your argument is circular. If you define "resistance" as the ratio of > voltage to current, possibly varying with time, voltage, or current, > then sure, Ohm's Law works; but then Ohm's Law becomes a tautology, > trivially satisfied by everything and predicting nothing. The "law" > is a useful law only in circumstances where voltage and current do not > alter the electrical properties of the material; then it becomes an > observation that current is proportional to voltage for all voltages > and currents within some large range of applicability. That > observation is not valid for the situation described here. Ohm's law describes the relationship between electrical current, resistance, and potential in a circuit. That's it. Any member of that circuit can vary at any given time and place, but the defined relationship remains intact, forcing a change in another member. -- Skitt (AmE)
From: Doctroid on 29 Mar 2010 13:36 In article <hoqn1v$uu9$1(a)news.albasani.net>, "Skitt" <skitt99(a)comcast.net> wrote: > Doctroid wrote: > > "Skitt" wrote: > >> Doctroid wrote: > >>> Peter Moylan wrote: > >>>> PaulJK wrote: > >>>>> Doctroid wrote: > >>>>>> "PaulJK" wrote: > > >>>>>>> Voltage and current are proportional to each other. > >>>>>>> It is therefore sufficient to say that damage is proportional > >>>>>>> to one of them. > >>>>>> Only in materials and voltage/current ranges where Ohm's "law" is > >>>>>> obeyed. And if damage is occurring, it probably isn't. > >>>>> > >>>>> Ohm's law is always obeyed in all aparatus made by humans. > >>>>> > >>>> Except when it isn't - which is most of the time. > >>>> > >>>> It's true that a great many resistors are nearly linear, i.e. they > >>>> can be said to obey Ohm's law to a reasonable degree of accuracy, > >>>> provided that you don't go beyond their design limits. > >>>> > >>>> It's equally true that some resistive devices are *deliberately* > >>>> made to be nonlinear. A semiconductor diode, for example, would be > >>>> totally useless if it obeyed Ohm's law. > >>> > >>> Besides which, the subject under discussion was not human-made > >>> apparatus, but humans. > >>> > >>> And again, under conditions where the electric current is causing > >>> tissue damage, Ohm's "law" doesn't really apply. > >> > >> Ohms law applies quite well. It is the encountered resistance that > >> is changing as the skin (of much higher resistance than the mushy > >> and moist innards) is damaged. > > > > Your argument is circular. If you define "resistance" as the ratio of > > voltage to current, possibly varying with time, voltage, or current, > > then sure, Ohm's Law works; but then Ohm's Law becomes a tautology, > > trivially satisfied by everything and predicting nothing. The "law" > > is a useful law only in circumstances where voltage and current do not > > alter the electrical properties of the material; then it becomes an > > observation that current is proportional to voltage for all voltages > > and currents within some large range of applicability. That > > observation is not valid for the situation described here. > > Ohm's law describes the relationship between electrical current, resistance, > and potential in a circuit. That's it. Any member of that circuit can vary > at any given time and place, but the defined relationship remains intact, > forcing a change in another member. If that is so, then please tell me how you define "resistance". -- Sig available on request. - Doctroid
From: Skitt on 29 Mar 2010 13:44
Doctroid wrote: > "Skitt" wrote: >> Doctroid wrote: >>> "Skitt" wrote: >>>> Doctroid wrote: >>>>> Peter Moylan wrote: >>>>>> PaulJK wrote: >>>>>>> Doctroid wrote: >>>>>>>> "PaulJK" wrote: >>>>>>>>> Voltage and current are proportional to each other. >>>>>>>>> It is therefore sufficient to say that damage is proportional >>>>>>>>> to one of them. >>>>>>>> Only in materials and voltage/current ranges where Ohm's "law" >>>>>>>> is obeyed. And if damage is occurring, it probably isn't. >>>>>>> >>>>>>> Ohm's law is always obeyed in all aparatus made by humans. >>>>>>> >>>>>> Except when it isn't - which is most of the time. >>>>>> >>>>>> It's true that a great many resistors are nearly linear, i.e. >>>>>> they can be said to obey Ohm's law to a reasonable degree of >>>>>> accuracy, provided that you don't go beyond their design limits. >>>>>> >>>>>> It's equally true that some resistive devices are *deliberately* >>>>>> made to be nonlinear. A semiconductor diode, for example, would >>>>>> be totally useless if it obeyed Ohm's law. >>>>> >>>>> Besides which, the subject under discussion was not human-made >>>>> apparatus, but humans. >>>>> >>>>> And again, under conditions where the electric current is causing >>>>> tissue damage, Ohm's "law" doesn't really apply. >>>> >>>> Ohms law applies quite well. It is the encountered resistance that >>>> is changing as the skin (of much higher resistance than the mushy >>>> and moist innards) is damaged. >>> >>> Your argument is circular. If you define "resistance" as the ratio >>> of voltage to current, possibly varying with time, voltage, or >>> current, then sure, Ohm's Law works; but then Ohm's Law becomes a >>> tautology, trivially satisfied by everything and predicting >>> nothing. The "law" is a useful law only in circumstances where >>> voltage and current do not alter the electrical properties of the >>> material; then it becomes an observation that current is >>> proportional to voltage for all voltages and currents within some >>> large range of applicability. That observation is not valid for the >>> situation described here. >> >> Ohm's law describes the relationship between electrical current, >> resistance, and potential in a circuit. That's it. Any member of >> that circuit can vary at any given time and place, but the defined >> relationship remains intact, forcing a change in another member. > > If that is so, then please tell me how you define "resistance". Resistance is the opposition offered by a body or substance to the passage through it of an electric current. -- Skitt (AmE) |