# Finding Closed Surfaces for Point Charge at Origin

• august_2007

#### august_2007

If there's a point charge at the origin, I want to find two closed surfaces such that the flux through one of them is zero while the other is not.

I know this may seem trivial but I just want to make sure I understand the question.

My answer would be that to get a zero flux, the closed surface must NOT enclose the charge at the origin while for the non-zero flux, the surface must enclose the charge; is this OK?

Yes.

## 1. What is the concept of "Finding Closed Surfaces for Point Charge at Origin"?

The concept of "Finding Closed Surfaces for Point Charge at Origin" is a method used in electrostatics to determine the electric field at a point in space due to a point charge located at the origin. It involves using Gauss's law and integrating the electric field over a closed surface surrounding the point charge.

## 2. Why is it important to find closed surfaces for point charges at the origin?

Finding closed surfaces for point charges at the origin is important because it allows us to accurately calculate the electric field at a point due to a point charge. This is useful in understanding the behavior of electric charges and in solving practical problems involving electric fields.

## 3. What types of surfaces can be used to enclose a point charge at the origin?

The closed surfaces that can be used to enclose a point charge at the origin include spheres, cubes, cylinders, and any other shape that completely surrounds the point charge. The surface must be closed, meaning it has no holes or openings.

## 4. How do you determine the direction of the electric field using this method?

The direction of the electric field can be determined by using the right-hand rule. If the closed surface is a sphere, the direction of the electric field will be radial, pointing away from the point charge if it is positive and towards the point charge if it is negative. If the closed surface is a cube or other shape, the direction of the electric field will be perpendicular to the surface at each point.

## 5. Are there any limitations to using this method?

One limitation of using this method is that it only applies to point charges at the origin. The electric field due to a point charge at any other location would require a different method. Additionally, the closed surface must be chosen carefully to accurately represent the electric field at the point of interest. In some cases, it may be difficult to find a suitable closed surface that surrounds the point charge.