Definition of Electric charge: when placed in an electromagnetic field, the physical property of matter known as electric charge causes it to experience a force. There might be a positive or negative electric charge (commonly carried by protons and electrons respectively. Charges with comparable charges repel one other, while charges with dissimilar charges attract each other.
An object that has no net charge is referred to as “neutral.” Classical electrodynamics refers to early knowledge of how charged substances interact, and it is still an accurate issue that does not necessitate the use of quantum effects. Electric charge is a conserved property; the net charge of an isolated system, which is the sum of positive and negative charges, cannot change. Subatomic particles carry an electric charge.
In ordinary matter, electrons carry a negative charge, while protons carry a positive charge in the nuclei of atoms. If a piece of matter has more electrons than protons, it has a negative charge; if there are fewer, it has a positive charge; and if there are equal numbers, it is neutral.
Electric fields are created by electric charge. A moving charge can also produce a magnetic field. The electromagnetic (or Lorentz) force, one of the four fundamental forces in physics, is generated by the interaction of electric charges with an electromagnetic field (combination of electric and magnetic fields). Quantum electrodynamics is the study of photon-mediated interactions between charged particles.
The coulomb (C) is the SI-derived unit of electric charge, named after French physicist Charles-Augustin de Coulomb. In electrical engineering, the ampere-hour is also extensively used (Ah). In physics and chemistry, the elementary charge (e) is often employed as a unit. In chemistry, the Faraday constant is used to compute the charge on a mole of electrons.
Even when the net charge of an object is zero, the charge can be distributed non-uniformly within the object (e.g., due to an external electromagnetic field, or bound polar molecules). The object is said to be polarised in such cases. The charge produced by polarization is known as a bound charge, whereas the charge produced on an object by electrons gained or lost from outside the object is known as free charge. Electric current is the movement of electrons in conductive metals in a specific direction.
The fundamental property of matter that exhibits electrostatic attraction or repulsion in the presence of other matter with charge is a charge. Electric charge is a property shared by many subatomic particles. The charges of free-standing particles are integer multiples of the elementary charge e; this is referred to as quantization of electric charge. Michael Faraday was the first to notice the discrete nature of electric charge in his electrolysis experiments. Robert Millikan’s oil drop experiment directly demonstrated this fact by measuring the elementary charge.
By convention, an electron’s charge is negative, e, whereas a proton’s charge is positive, +e. Charged particles with the same sign repel one another, while charged particles with different signs attract. Coulomb’s law states that the electrostatic force between two particles is proportional to the product of their charges and inversely proportional to the square of their distance. An antiparticle’s charge is equal to that of the corresponding particle, but with the opposite sign. A macroscopic object’s electric charge is the sum of the electric charges of the particles that make it up. Because matter is made up of atoms, and atoms typically have an equal number of protons and electrons, their charges cancel out, yielding a net charge of zero, rendering the atom neutral.
An ion is an atom (or group of atoms) that has lost one or more electrons, resulting in a net positive charge (cation), or gained one or more electrons, resulting in a net negative charge (anion) (anion). Monatomic ions are formed from single atoms, whereas polyatomic ions are formed from two or more bonded atoms, yielding an ion with a positive or negative net charge in each case. An electric field is created by a positive electric charge. A negative electric charge produces an electric field.
A positive electric charge induces a field, while a negative electric charge induces a field (right). Constituent atoms and ions typically combine to form structures composed of neutral ionic compounds electrically bound to neutral atoms during the formation of macroscopic objects. Thus, macroscopic objects tend to be neutral in general, but they are rarely perfectly net neutral.
Electric charges are carried by subatomic particles. In the nuclei of atoms, electrons have a negative charge while protons have a positive charge.
When two currents meet at a junction, the resultant current is an algebraic sum rather than a vector sum. As a result, electric current is a scalar quantity.
When there are more electrons than protons in a substance, it is said to have a negative charge.