Planar symmetry

Definition

Planar symmetry refers to a system or object that is invariant under reflection across a plane. In physics, it simplifies the application of Gauss’s Law by reducing the complexity of the electric field calculations.

5 Must Know Facts For Your Next Test

1. In systems with planar symmetry, the electric field is perpendicular to the plane of symmetry and has the same magnitude at all points equidistant from the plane.
2. Gauss’s Law can be applied to planar symmetry by choosing a Gaussian surface that aligns with this symmetry, often a pillbox shape.
3. The flux through each face of a Gaussian surface in planar symmetry can be used to calculate the electric field more easily.
4. Planar symmetry is commonly found in infinite sheets of charge, where edge effects are negligible.
5. The resulting electric field due to a uniformly charged infinite plane is constant and does not depend on distance from the plane.

Review Questions

• How does planar symmetry simplify the application of Gauss's Law?
• What type of Gaussian surface is typically used for systems with planar symmetry?
• Describe how the electric field behaves in relation to an infinite sheet of charge exhibiting planar symmetry.

Related terms

Gaussian Surface: An imaginary closed surface used in Gauss's Law to calculate electric fields; chosen based on system symmetries.

Electric Flux: A measure of the distribution of an electric field over a given area; calculated as $\Phi = \mathbf{E} \cdot \mathbf{A}$.

Symmetry: In physics, it refers to invariance under certain transformations, such as rotation, reflection, or translation.