Lines of Force: An imaginary line drawn in an electric
field such that the tangent drawn to the line of force at any point gives the
direction of the electric field at that point.
Electric Flux: The electric flux through a point is
defined as the product of area and the component of electric intensity normal
to the area.
Tube of Force: A tubular shape bounded by a group of lines
of force starting from an area A1 of a positively charged surface
and ending on an area A2 of a negatively charged surface.
Tube of Induction: In a medium other than air or vacuum,
a tube of force is called a tube of induction.
Electric Induction: The number of tubes of induction passing
normally through unit area around a point in the electric field is called the
normal electric induction.
Gaus's Theorem: Gaus's
theorem states that the total normal electric induction over a closed surface
is equal to the net electric charge enclosed by the surface.
Capacitance (or Capacity): Capacitance of a
conductor is the ratio of its charge to its potential.
Farad: It is the unit of capacitance in the S.I.
system. It is the capacitance of a conductor whose potential increases by one
volt when it is given a charge of one coulomb.
Capacitor (Condenser): An arrangement of two conductors
separated by an insulating medium.
Coulomb's Law: Coulomb's law states that the force of interaction
between two point charges is directly proportional to the product of the
magnitude of the two charges and is inversely proportional to the square of
the distance between them.
Electric Intensity (E): The electric
intensity at a point in an electric field is defined as the force acting on
unit positive charge placed at that point.
Electric Potential(V): The electric
potential at a point in an electric field is defined as the work done in
bringing unit positive charge from infinity to that point.