n0_3sc said:Can anyone explain how to go from:
[tex]I_s = \frac{nc\epsilon}{2} |E|^2 [/tex]
to
[tex]I_s = \frac{nc}{8\pi} |E|^2 [/tex]
That means [tex] \epsilon [/tex] is [tex] \frac{1}{4\pi} [/tex]...I can't find that anywhere.
The intensity of electric field is a measure of the strength of an electric field at a given point in space. It is a vector quantity that represents the force that a unit positive charge would experience if placed in that electric field.
The intensity of electric field is calculated by dividing the force exerted on a test charge by the magnitude of the test charge. This can be expressed mathematically as E = F/q, where E is the intensity of electric field, F is the force exerted on the test charge, and q is the magnitude of the test charge.
The intensity of electric field is affected by the magnitude and direction of the electric charge creating the field, the distance between the charges, and the medium through which the electric field is passing. In addition, the presence of other charges in the vicinity can also affect the intensity of electric field.
The SI unit of intensity of electric field is newtons per coulomb (N/C). However, it can also be expressed in volts per meter (V/m) or electron volts per meter (eV/m).
The intensity of electric field can be represented graphically using electric field lines. These are lines that indicate the direction and strength of the electric field. The closer the lines are together, the stronger the electric field. The direction of the field is indicated by the direction of the lines, which point away from positive charges and towards negative charges.