Electric charges and fields

Introduction:
State the coulomb’s law or Coulomb’s law of electrostatics: Coulomb’s law states that the magnitude of the electrostatic force of attraction or repulsion between two point charges is directly proportional to the product of the magnitudes of charges and inversely proportional to the square of the distance between them. There are only two kinds of charges, which we call positive and negative. Like charges repel, unlike charges attract. As usual, there will be some force of attraction/ repulsion between two charges. The majority of charge in nature is carried by protons, whereas the negative charge of each electron is determined by experiment to have the same magnitude, which is also equal to that of the positive charge of each proton.

An ion is an atom or molecule that has a nonzero total charge because of having unequal numbers of electrons along with the protons. The SI unit of charge is given by a coulomb (C) also, one coulomb is equal to the amount of charge from a current of one ampere flowing for one second. All charge resides on outer surface so that according to Gauss law, the electric field inside a shell is zero. Also, a moving charge produces both electric and magnetic fields. A stationary charge produces only an electric field in the surrounding distance. If the charge is moving, a magnetic field is also produced.

Thus, the electric flux through the surface doesn’t depend on the shape, size or area of a surface, but it depends on the amount of charge enclosed by the surface.

The electric field, almost like the electrical force, obeys the principle of superposition. The world could also be a vector by definition, it points away from positive charges and toward negative charges.

List of topics according to NCERT and JEE Main/NEET syllabus:

1. Electrostatic force between two and more charges; Coulomb’s law.
2. Continuous charge distribution.
3. Electric field and Electric field lines;
4. Motion of charged particle in Electric field
5. Electric dipole and electric field due to a dipole
6. Torque on a dipole in uniform electric field
7. Electric potential and potential difference
8. Equipotential surface
9. Electric potential energy of a system of charges in electrostatic field
10. Gauss’ theorem and its applications

Related Topics,

Important concepts and Laws:

The important concepts in electric charges and fields are electric charges and their conservation which consist of what is charge; charging by induction; Quantization of energy; conservation of charges. Then Coulomb’s law along with Coulomb’s inverse square law, from which the derivation for Coulomb’s law is asked, along with its SI unit and definition of dielectric constant. The principle of superposition principle; forces between multiple charges; continuous distribution of charges (Linear charge; Surface charge; Volume charge density) are frequently asked.

The derivation for electric dipole; electric field intensity due to an electric dipole at a point on the equatorial and electric field intensity at a general point due to short electric dipole along with torque on a dipole in uniform electric field. Generally, questions about electric flux as short notes and for SI units and dimensions are frequently asked.. The electric field due to a dipole at a point on the axis of an electric dipole is given by two equal and opposite charges separated by some distance constitute a dipole and about the electric field strength due to a dipole, far away, is always proportional to the dipole moment and inversely proportional to the cube of the distance.

Some important concepts are that we can use the superposition principle for computing net force; net field; net flux; at the observation point P due to any configuration of charges. If the electric field intensity is the same both in magnitude and direction throughout then the electric field is said to be uniform. Uniform electric fields are represented by equi-distance parallel lines. The last but important theorem is Gauss’s theorem and its application and the application which are electric field due to an infinitely long straight wire, electric field due to uniformly charged infinite plane sheet and electric field due to uniformly charged spherical shape are the few application which is expected from students to explain with their appropriate diagram.

NCERT Notes Subject wise link:

• NCERT Notes for class 12 Physics.
• NCERT Notes for class 12 Chemistry.
• NCERT Notes for class 12 Mathematics.
• NCERT Notes for class 12 Biology.

Importance of Electric charges and fields class 12:

Class 12 Physics Chapter 1 is taken under consideration to be the foremost important part for school students aiming to clear the NEET exam. In CBSE Class 12 Physics chapter 1, several important derivations and formulas are presented to the students which are crucial to forming the essential skills required for a medical & engineering career. NCERT Class 12 syllabus has various important topics, diagrams and definitions that students require to be thorough with to be able to score well within the category 12 board exam. To secure good marks in class 12, students are required to arrange thoroughly and practice with NCERT Class 12 Chapter one Electric Charges & Fields Physics Marks Wise Question.

• NCERT solutions for class 12 physics chapter 1 Electric Charges and Fields.
• NCERT exemplar solutions for class 12 physics chapter 1 Electric Charges and Fields.
• NCERT notes for class 12 physics chapter 1 Electric charges and fields.
  

NCERT Solutions Subject wise link:

• NCERT solutions for class 12 Physics.
• NCERT solutions for class 12 Chemistry.
• NCERT solutions for class 12 Mathematics.
• NCERT solutions for class 12 Biology.
  

NCERT Exemplar Solutions Subject wise link:

• NCERT exemplar solutions for class 12 Physics.
• NCERT exemplar solutions for class 12 Chemistry.
• NCERT exemplar solutions for class 12 Mathematics.
• NCERT exemplar solutions for class 12 Biology.