What does ΦE denote in Gauss's law?

What does ΦE denote in Gauss's law?

• A. Electric potential
• B. Electric charge
• C. Magnetic flux
• D. Electric field flux

Answer: (D)

Φ_E is the electric flux through a surface. It measures how much electric field passes through that surface, defined by the surface integral ∮ E · dA with dA oriented outward on a closed surface. This quantity is what Gauss's law relates to the enclosed charge: Φ_E = Q_enclosed/ε0. It’s not electric potential, which is a scalar quantity denoted V or φ at a point; it’s not electric charge, which is the source quantity Q; and it’s not magnetic flux, which involves the magnetic field B and is described by Φ_B. The idea of flux captures the passage of the electric field through a surface, including the sign based on outward orientation.

Φ_E is the electric flux through a surface. It measures how much electric field passes through that surface, defined by the surface integral ∮ E · dA with dA oriented outward on a closed surface. This quantity is what Gauss's law relates to the enclosed charge: Φ_E = Q_enclosed/ε0. It’s not electric potential, which is a scalar quantity denoted V or φ at a point; it’s not electric charge, which is the source quantity Q; and it’s not magnetic flux, which involves the magnetic field B and is described by Φ_B. The idea of flux captures the passage of the electric field through a surface, including the sign based on outward orientation.