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This seems wrong but I do not have the expertise to confidently correct it: "The number 2997924580 is 10 times the value of the speed of light expressed in meters/second or, in other words, the speed of light in centimeters per second." That number is indeed 10 times the speed of light: 299792458 m/s. But then it is therefore in dm/s, because there are 100 cm in 1 m, not 10. Can someone clarify this for me or fix this? Thank you. — Preceding unsigned comment added by 86.143.159.70 ( talk) 19:43, 3 January 2020 (UTC)
One Statcoulomb is NOT equal to 0.1/c (c expressed in cgs units). Try this: use the 0.1/c factor to convert the elementary charge from Coulomb to Statcoulomb. You will be off by a factor of 1/100. The appropriate correction factor is 10/c. —Preceding
unsigned comment added by
75.13.69.16 (
talk)
16:56, 14 March 2008 (UTC)
I agree with this, I worked through Coulomb's Law in detail. The article states that 1 C = 2997924580 statC, this IS correct. However I will correct where it says c expressed in cgs, it is in m/s. —Preceding unsigned comment added by 121.44.221.75 ( talk) 11:32, 10 October 2008 (UTC)
I have changed this:
"Note that in order for the Coulomb's law formula to work using the electrostatic cgs system, the dimension of electrical charge must be [mass]1/2 [length]3/2 [time]-2."
to this:
"Note that in order for the Coulomb's law formula to work using the electrostatic cgs system, the dimension of electrical charge must be [mass]1/2 [length]3/2 [time]-1."
That is, I'm replacing a 1/(t^2) with just a 1/t because I think person who wrote the original version missed a square root when doing the algebra.
I corrected the hyperlink "electrostatic constant" to the article on permittivity, originally directed to "proportionality constant". Gp4rts ( talk) 07:09, 22 September 2008 (UTC)
Firstly I must admit that I know nothing about cgs units. I am a professional engineer, and adhere firmly to the SI system, in conform with with the world-wide scientific community. For me cgs is obsolete. However, I am intrigued by the comments in the article on the dimensions of the Coulomb & Statcoulomb. Since charge is defined conceptually & qualitatively in both systems in terms of Coulomb's law (the force between 'charges'), it seems improbable that the quantities can actually be different - reflected in their having different dimensions. Quantities with different dimensions are physically not the same, and I feel that this cannot be the case with something as fundamental as electric charge.
Here is what is probably a naive resolution... Since the omission of the factor epsilon0 in the cgs expression of Coulomb's law is the culprit, could it be that the permittivity of free space in the cgs system is numerically 1, but nevertheless has dimensions - the same as those of epsilon0 in the SI ? Andrew Smith g4oep. — Preceding unsigned comment added by 82.37.131.61 ( talk) 09:50, 28 March 2017 (UTC)
Since the corresponding equations in different systems are not identical, the symbols in them must represent (slightly) different quantities, i.e. different mathematical models of invariant physical phenomena.
In these relations we compare two corresponding quantities, i.e. an e.s. quantity and the corresponding e.m. quantity, describing the same real physical situation. Thus, for example, the relation between the corresponding current quantities Ie and Im can be easily found by writing down Ampère's force law between two parallel conductors in the e.s. and in the e.m. system: in the e.s. system this reads in vacuum … If we compare this with the corresponding equation … of the e.m. system we obtain . This shows again that Im and Ie are really different quantities differing by a factor c.
who did this calculation?
As far as I can calculate: m N½. There seems rather some magic with speed of light (10 c) in those numbers ... The other conversion is similarly funny:
by my calculation : m N½. Ra-raisch ( talk) 22:29, 12 August 2017 (UTC)
so if I understand correctly, the conversions should be
Ra-raisch ( talk) 09:07, 13 August 2017 (UTC)
I wiped bollocks out, which originated from years of clueless editing. No prejudice against reinstating some old pieces by an expert editor, just note that [1] by Sbyrnes321 explicitly states that “C” (presumably coulomb) may be used as a unit of electric flux. Beware! Incnis Mrsi ( talk) 07:05, 1 September 2019 (UTC)
This
level-5 vital article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||
|
This seems wrong but I do not have the expertise to confidently correct it: "The number 2997924580 is 10 times the value of the speed of light expressed in meters/second or, in other words, the speed of light in centimeters per second." That number is indeed 10 times the speed of light: 299792458 m/s. But then it is therefore in dm/s, because there are 100 cm in 1 m, not 10. Can someone clarify this for me or fix this? Thank you. — Preceding unsigned comment added by 86.143.159.70 ( talk) 19:43, 3 January 2020 (UTC)
One Statcoulomb is NOT equal to 0.1/c (c expressed in cgs units). Try this: use the 0.1/c factor to convert the elementary charge from Coulomb to Statcoulomb. You will be off by a factor of 1/100. The appropriate correction factor is 10/c. —Preceding
unsigned comment added by
75.13.69.16 (
talk)
16:56, 14 March 2008 (UTC)
I agree with this, I worked through Coulomb's Law in detail. The article states that 1 C = 2997924580 statC, this IS correct. However I will correct where it says c expressed in cgs, it is in m/s. —Preceding unsigned comment added by 121.44.221.75 ( talk) 11:32, 10 October 2008 (UTC)
I have changed this:
"Note that in order for the Coulomb's law formula to work using the electrostatic cgs system, the dimension of electrical charge must be [mass]1/2 [length]3/2 [time]-2."
to this:
"Note that in order for the Coulomb's law formula to work using the electrostatic cgs system, the dimension of electrical charge must be [mass]1/2 [length]3/2 [time]-1."
That is, I'm replacing a 1/(t^2) with just a 1/t because I think person who wrote the original version missed a square root when doing the algebra.
I corrected the hyperlink "electrostatic constant" to the article on permittivity, originally directed to "proportionality constant". Gp4rts ( talk) 07:09, 22 September 2008 (UTC)
Firstly I must admit that I know nothing about cgs units. I am a professional engineer, and adhere firmly to the SI system, in conform with with the world-wide scientific community. For me cgs is obsolete. However, I am intrigued by the comments in the article on the dimensions of the Coulomb & Statcoulomb. Since charge is defined conceptually & qualitatively in both systems in terms of Coulomb's law (the force between 'charges'), it seems improbable that the quantities can actually be different - reflected in their having different dimensions. Quantities with different dimensions are physically not the same, and I feel that this cannot be the case with something as fundamental as electric charge.
Here is what is probably a naive resolution... Since the omission of the factor epsilon0 in the cgs expression of Coulomb's law is the culprit, could it be that the permittivity of free space in the cgs system is numerically 1, but nevertheless has dimensions - the same as those of epsilon0 in the SI ? Andrew Smith g4oep. — Preceding unsigned comment added by 82.37.131.61 ( talk) 09:50, 28 March 2017 (UTC)
Since the corresponding equations in different systems are not identical, the symbols in them must represent (slightly) different quantities, i.e. different mathematical models of invariant physical phenomena.
In these relations we compare two corresponding quantities, i.e. an e.s. quantity and the corresponding e.m. quantity, describing the same real physical situation. Thus, for example, the relation between the corresponding current quantities Ie and Im can be easily found by writing down Ampère's force law between two parallel conductors in the e.s. and in the e.m. system: in the e.s. system this reads in vacuum … If we compare this with the corresponding equation … of the e.m. system we obtain . This shows again that Im and Ie are really different quantities differing by a factor c.
who did this calculation?
As far as I can calculate: m N½. There seems rather some magic with speed of light (10 c) in those numbers ... The other conversion is similarly funny:
by my calculation : m N½. Ra-raisch ( talk) 22:29, 12 August 2017 (UTC)
so if I understand correctly, the conversions should be
Ra-raisch ( talk) 09:07, 13 August 2017 (UTC)
I wiped bollocks out, which originated from years of clueless editing. No prejudice against reinstating some old pieces by an expert editor, just note that [1] by Sbyrnes321 explicitly states that “C” (presumably coulomb) may be used as a unit of electric flux. Beware! Incnis Mrsi ( talk) 07:05, 1 September 2019 (UTC)