Electric Field Density

Hi folks,

I was hoping someone could point me to a web site that would help me solve the following:

Given the potential function V = 4x - 4y Volts in free space, find the electric field density

I am not looking the problem solved, but somewhere on the internet that could help me solve it.

I have done a search, but nothing seems to come up with anything close to the question.

Many thanks in advance.

Abbsdad,

I was hoping someone could point me to a web site that would help me solve the following:

Given the potential function V = 4x - 4y Volts in free space, find the electric field density

Click to expand...

I think you mean electric field intensity, not density. There is a quantity called electric flux density, but I dont think that is what you mean, because you refer to a potential function in free space.

Electric field intensity is the force and direction of a unit positive charge in a electric field. It takes energy to move charges against a electric field, and energy is returned when the charges move with an electric field. The electric potential function you gave is the energy per unit charge from the origin of the coordinate system. Its MKS units are volts or joules/coulomb. As you can see from the link, the potential difference from point to point is the line integral of the electric field intensity from one point to another. Inversely, the electric field intensity is the gradient of the electric potential function. For one dimension, the gradient is simply the derivative with respect to distance. That is how they are related.

It would be wise for you to obtain a good book on electrostatics. And you won't develop a deep understanding of this subject until you to get up to speed on vector calculus.

Electric potential - Wikipedia, the free encyclopedia

Ratch

Abbsdad,

You are welcome.

Ratch

Hi Ratch,

Many thanks for the reply.

One thing is still puzzling me. What is volts in "free space"

Many thanks, Abbsdad

Abbsdad ,

One thing is still puzzling me. What is volts in "free space"

Click to expand...

Free space is a volume where no material exists. That means a perfect vacuum devoid of all mass. If a dielectric material exists within a electric field, then the material can become polarized, and affect the direction and magnitude of the electric field intensity. As I said before, a good textbook on electrostatics and a knowledge of vector calculus are your two best friends in this matter.

Ratch

Hi Ratch,

Many thanks.

Abbsdad

you can use the following formula for get field intensity-
E= - gradient of potential
then can find out field density by following formula-
D= eE(e= epsilon)

oh it is mentioned free space so u can use epsilon not , ie ε0 = (8.854 187 817)*10-12 F/m.

Hi Samina,

Thanks for the reply.

Abbsdad