Electric Charges & Fields
Class 12 · Electric Charges & Fields
Gauss's Law
Drag a charge in/out of a Gaussian sphere. Φ = Q_enc/ε₀ regardless of position inside.
Key Notes
01
Total flux through a closed surface = (charge enclosed)/ε₀.
02
Charges OUTSIDE the closed surface contribute zero net flux.
03
Used to find E for symmetric distributions: spherical, cylindrical, planar.
Formulas
Gauss's law
One of Maxwell's equations.
Important Points
Choose Gaussian surface so E is constant in magnitude and ∥ or ⟂ to surface.
Symmetry is essential — Gauss's law is true always but only useful with high symmetry.
Gauss's Law notes from sciphylab (also known as SciPhy, SciPhy Lab, SciPhy Labs, Physics Lab). Class 12 physics revision for JEE Mains, JEE Advanced, NEET UG, AP Physics 1/2/C, SAT, and CUET-UG.