### Correct Option: B ### Explanation of the Correct Answer **Electric Flux Definition:** Electric flux (\( \Phi_E \)) through a surface is defined as the product of the electric field (\( E \)) and the area (\( A \)) of the surface, as well as the cosine of the angle (\( \theta \)) between the electric field lines and the normal (perpendicular) to the surface. The formula for electric flux is given by: \[ \Phi_E = E \cdot A \cdot \cos(\theta) \] **Understanding the Scenario:** In this question, we are considering a surface that is oriented **perpendicular** to the electric field lines. This means that the angle \( \theta \) between the electric field and the normal to the surface is \( 0^\circ \). **Calculating the Electric Flux:** When \( \theta = 0^\circ \), the cosine of \( 0^\circ \) is 1: \[ \cos(0^\circ) = 1 \] Thus, the formula for electric flux simplifies to: \[ \Phi_E = E \cdot A \cdot 1 = E \cdot A \] This means that the electric flux through the surface is equal to the product of the electric field strength and the area of the surface. Therefore, the correct answer is **B**. ### Explanation of Why Other Options Are Incorrect **Option A: Zero** - This option suggests that the electric flux is zero. This is incorrect because, when the surface is perpendicular to the electric field, the electric field lines pass directly through the surface, contributing to a non-zero flux. Only if the surface were parallel to the field lines would the flux be zero. **Option C: Equal to the electric field strength divided by the area** - This option implies a relationship that does not align with the definition of electric flux. Electric flux is not defined as the electric field strength divided by the area. Instead, it is the product of the electric field strength and the area when the surface is perpendicular to the field lines. **Option D: Equal to the area only** - This option suggests that the electric flux is equal to the area alone, which is incorrect. The electric flux depends on both the electric field strength and the area. The area alone does not account for the influence of the electric field. ### Summary of Key Points - **Electric Flux Formula:** \( \Phi_E = E \cdot A \cdot \cos(\theta) \) - **Perpendicular Orientation:** When the surface is perpendicular to the electric field, \( \theta = 0^\circ \) and \( \cos(0^\circ) = 1 \). - **Resulting Flux:** The electric flux is equal to the product of the electric field strength and the area (\( \Phi_E = E \cdot A \)). - **Common Pitfall:** Confusing the orientation of the surface with the resulting electric flux; remember that only perpendicular surfaces yield maximum flux. This thorough understanding of electric flux will help you tackle similar questions in your physics exams effectively!