ElectroMagnetic Theory Concepts & Solved Numericals

- Gauss law is one of the fundamental laws of Electrostatics. - It states that “The net electric flux emanating or coming from a close surface S is equal to the total charge contained within the volume V bounded by that surface.” We know, Therefore Ψ = Q enc Hence Gauss law also states that  “The total electric flux Ψ through any closed surface is equal to the enclosed electric charge.” - Charge contained in a volume is given as: dQ = ρ v dv → Q = ∫ V ρ v dv Hence we have,   Applying Divergence theorem we have, Comparing the above two equations, we have And hence   ∇ . D = ρ v This equation is called the 1 st Maxwell's equation of electrostatics. - Gauss law is an easy way of finding electric field for some symmetric problems in electrostatics. - Gauss law relates the electric field at points on a closed Gaussian surface to the net charge enclosed by that surface. - One thing to remember ...

- Electric field due to a charge is the space around the unit charge in which it experiences a force. - Electric field intensity or the electric field strength at a point is defined as the force per unit charge. Mathematically, E = F / Q  OR F = E Q - The force on charge Q is the product of a charge (which is a scalar) and the value of the electric field (which is a vector) at the point where the charge is located. - Hence force will be either parallel or anti-parallel to the Electric field intensity. (i.e. Q > 0) the force F points in the same direction as the electric field E. - If the charge is negative (i.e. Q < 0) the force F points in the opposite direction as the electric field E. - Electric field intensity (E) at point r due to a point charge Q located at a point with position vector r 1 is given as: Similarly for N point charges Q 1 , Q 2 ….Q n located at points with position vectors r 1 , r 2 ,….r n , the electric fiel...