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Chen
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Hi,
What are the dimensions of K? Is it (Force x Length^2 / Charge^2), or is it dimension-less?
Thanks.
What are the dimensions of K? Is it (Force x Length^2 / Charge^2), or is it dimension-less?
Thanks.
Chen said:What are the dimensions of K? Is it (Force x Length^2 / Charge^2), or is it dimension-less?
Ok, so you say in CGS units [tex]\epsilon_0[/tex] is dimensionless. But then, what are the dimensions of [tex]\mu_0[/tex]? Because if [tex]c = \frac{1}{\sqrt{\epsilon_0 \mu_0}}[/tex] (and I assume this still holds in CGS units) then [tex]\mu_0[/tex] must have a dimension of (time/length)2, but I know that in MKS units [tex]\mu_0[/tex] is inductance per length. So how does this work out...?rbj said:in the CGS electrostatic units they define the Coulomb Force Constant to be the dimensionless 1 ([tex] \epsilon_0 = \frac{1}{4 \pi} [/tex] in cgs). that results in the dimension of electric charge being length / time x sqrt(length x mass) or velocity x (length x mass)^(1/2).
yer welcome.Chen said:Thanks for that, rbj, that's exactly the kind of answer I was looking for.
Ok, so you say in CGS units [tex]\epsilon_0[/tex] is dimensionless. But then, what are the dimensions of [tex]\mu_0[/tex]? Because if [tex]c = \frac{1}{\sqrt{\epsilon_0 \mu_0}}[/tex] (and I assume this still holds in CGS units)
then [tex]\mu_0[/tex] must have a dimension of (time/length)2, but I know that in MKS units [tex]\mu_0[/tex] is inductance per length. So how does this work out...?
Chen said:On the same subject, what's the reason for the difference in equations for the magnetic force? In MKS: [tex]q\vec v \times \vec B[/tex], in cgs: [tex]\frac{q}{c}\vec v \times \vec B[/tex].
Chen said:Thank you very much!
The constant K in Coulomb's Law is approximately 8.99 x 10^9 Nm^2/C^2. This value is often referred to as the permittivity of free space.
The units of the constant K in Coulomb's Law are Newton meters squared per coulomb squared (Nm^2/C^2). This unit is also equivalent to Farads per meter (F/m).
The constant K in Coulomb's Law represents the strength of the electric force between two charged particles. It is a fundamental constant in electromagnetism and is used to calculate the force between two point charges.
The larger the value of the constant K, the stronger the electric force between two charged particles. This means that as the distance between the charged particles decreases, the force between them increases significantly.
Yes, the constant K in Coulomb's Law is a universal constant and is always the same in a vacuum. However, in different mediums such as air or water, the value of K may change slightly due to the effects of permittivity of the medium.