Net charge enclosed by the cylinder is zero so net flux through the cylinder is zero.

## What is the net electric flux through the closed cylindrical surface?

E The **net electric flux through** a **closed cylindrical surface** is zero.

## What is the electric flux through the cylinder?

Electric Field of Line Charge

Considering a Gaussian surface in the form of a cylinder at radius r, the electric field has the same magnitude at every point of the cylinder and is directed outward. The electric flux is then **just the electric field times the area of the cylinder.**

## How do you find electric flux through a closed surface?

The flux Φ of the electric field →E through any closed surface S (a Gaussian surface) is equal to the net charge enclosed (qenc) divided by the permittivity of free space (ϵ0): **Φ=∮S→E⋅ˆndA=qencϵ0**.

## What is the flux through a closed surface?

The flux of a vector field through a closed surface is **always zero** if there is no source or sink of the vector field in the volume enclosed by the surface. The sources and sinks for the electric field are charges.

## When a cylindrical surface is completely inside the electric field?

Using the Gauss’s law , prove that the net charge enclosed by this cylindrical surface must be **zero**. Consider a cylinder placed in uniform electric field with its axis parallel to electric field intensity as shown in the figure. Electric flux through cylinder can be calculated as sum of flux through all the surfaces.

## Is flux dependent on distance?

**The flux doesn’t depend on the distance r**. We would get the same result no matter the size of the closed surface around the point charge.

## Why electric flux is zero in a closed surface?

Gauss’s law tells us that the electric flux through a closed surface is proportional to the net charge enclosed by the surface. Thus, the electric flux through the closed surface is zero **only when the net charge enclosed by the surface is zero**.

## What does it mean if the electric flux through a closed surface is negative?

**Field lines directed into a closed surface** are considered negative; those directed out of a closed surface are positive. If there is no net charge within a closed surface, every field line directed into the surface continues through the interior and is directed outward elsewhere on the surface.

## How do you find flux on a surface?

**Know the formula for electric flux.**

- The Electric Flux through a surface A is equal to the dot product of the electric field and area vectors E and A.
- The dot product of two vectors is equal to the product of their respective magnitudes multiplied by the cosine of the angle between them.