Problems In Electromagnetics Electrostatics
Concepts to remember for Electrostatics:

Coulomb’s law and its vector form: Remember that the force between two charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. The vector form of Coulomb’s law provides both the magnitude and direction of the force.

Electric field and electric potential: Understand that the electric field is a vector field that describes the strength and direction of the electric force at a given point in space. The electric potential, on the other hand, is a scalar quantity that represents the potential energy per unit charge at a point in space.

Relationship between electric field and electric potential: Remember that the electric field is the negative gradient of the electric potential. In other words, the electric field points in the direction of decreasing electric potential.

Electric flux and Gauss’s law: Grasp the concept of electric flux, which measures the amount of electric field passing through a surface. Gauss’s law states that the total electric flux through any closed surface is equal to the enclosed charge divided by the permittivity of free space.

Applications of Gauss’s law: Gauss’s law is a powerful tool for calculating electric fields in symmetric charge distributions. It can be used to find the electric field inside and outside of conductors and other shapes.

Electric potential energy and capacitance: Remember that the electric potential energy of a system of charges is the energy stored in the system due to the interactions between the charges. Capacitance is a measure of the ability of a system to store electric charge.

Capacitors and their types: Understand that capacitors consist of two conductors separated by an insulator. There are different types of capacitors, including parallelplate capacitors, cylindrical capacitors, and spherical capacitors.

Energy stored in a capacitor: Recall that the energy stored in a capacitor is directly proportional to the capacitance and the square of the potential difference across the capacitor.

Dielectric materials and their properties: Dielectric materials are insulators that can reduce the electric field within a capacitor without conducting electricity. Polarisation is the process by which dielectric materials reduce the electric field.

Polarisation of dielectric materials: Remember that when a dielectric material is placed in an electric field, its molecules become polarised, i.e., their positive and negative charges are separated, creating an internal electric field that opposes the external field.

Parallelplate capacitors and their capacitance: Understand the structure and formula for capacitance of parallelplate capacitors, consisting of two parallel conducting plates separated by a dielectric material.

Spherical capacitors and their capacitance: Grasp the structure and formula for capacitance of spherical capacitors, consisting of two concentric spherical conducting shells separated by a dielectric material.

Cylindrical capacitors and their capacitance: Understand the structure and formula for capacitance of cylindrical capacitors, consisting of two coaxial cylindrical conducting surfaces separated by a dielectric material.

Capacitance of a system of capacitors: Remember the formulas for calculating the total capacitance of capacitors connected in series and in parallel.

Electrostatic potential energy: Recall that the electrostatic potential energy of a system of charges is the sum of the electric potential energies of all the pairs of charges in the system.

Electric dipole and its electric potential: Understand the concept of an electric dipole, which consists of two opposite charges separated by a small distance. Remember the formula for the electric potential of a dipole at a point on the dipole axis.

Torque on an electric dipole in an electric field: Recall that an electric dipole experiences a torque when placed in an electric field, tending to align its dipole moment with the electric field.

Electric field of a dipole: Remember the formula for the electric field of a dipole at a point on the dipole axis and perpendicular to the dipole axis.

Electric potential of a dipole: Recall the formula for the electric potential of a dipole at a point on the dipole axis and perpendicular to the dipole axis.

Electrostatic induction: Grasp the process of electrostatic induction, where a charged object can induce the separation of charges in a neutral object without direct contact.

Charging by induction: Remember that charging by induction is a technique to charge an object without direct contact by bringing it near a charged object.

Faraday’s icepail experiment: Recall the significance of Faraday’s icepail experiment in demonstrating electrostatic induction and the properties of conductors and insulators.

Electrostatic machines: Understand the principles of electrostatic machines, such as the Wimshurst machine, that use electrostatic induction to generate static electricity.