Consider a cylindrical surface of radius R and length l in a uniform electric field E. Compute the electric flux if the axis of the cylinder is parallel to the field direction.

Explanation

To compute the electric flux through a cylindrical surface of radius \( R \) and length \( l \) in a uniform electric field \( E \) when the axis of the cylinder is parallel to the field direction, we can follow these steps:

### Step 1: Understand the Geometry
The cylindrical surface has two circular ends (top and bottom) and a curved surface. The electric field \( E \) is uniform and directed along the axis of the cylinder.

### Step 2: Identify the Surfaces
1. **Curved Surface**: The electric field lines are parallel to the axis of the cylinder, which means that the electric field is perpendicular to the normal of the curved surface.
2. **Circular Ends**: The electric field is perpendicular to the normal of the circular ends.
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