The surface shown is a square of side length a. What is the electric flux through the surface? π E a2 E a2 cos(θ) E a2 cos(90° + θ) E a2

The electric flux through a surface is given by the equation Φ = E * A * cos(θ), where E is the electric field, A is the area of the surface, and θ is the angle between the electric field direction and the normal to the surface.

In this case, the surface is a square with side length a, so the area A = a^2.

If the electric field is uniform and perpendicular to the surface, then θ = 0 degrees and cos(θ) = 1. Therefore, the electric flux through the surface is Φ = E * a^2.

If the electric field is at an angle θ to the normal of the surface, then the electric flux is Φ = E * a^2 * cos(θ).

If the electric field is parallel to the surface, then θ = 90 degrees and cos(θ) = 0. Therefore, the electric flux through the surface is Φ = 0.

If the electric field is at an angle of 90° + θ to the normal of the surface, then the electric flux is Φ = E * a^2 * cos(90° + θ).

So, the electric flux through the surface depends on the angle θ