Definitions [4]
“An electric line of force is an imaginary smooth curve drawn in an electric field along which a free, isolated positive charge moves. The tangent drawn at any point on the electric line of force gives the direction of the force acting on a positive charge placed at that point.”
Define ‘electric dipole’.
Two equal and opposite charges separated by a very small distance constitute an electric dipole.
Ex:- Carbondioxide, Water.
Define electrostatic potential.
The electric potential at a point P is equal to the work done by an external force to bring a unit positive charge with constant velocity from infinity to the point P in the region of the external electric field `vec"E"`.
Define ‘electrostatic potential energy’.
It is defined as the amount of work done in assembling the charges at their locations by bringing them in from infinity.
Key Points
- Electric field lines originate from positive charges and terminate on negative charges (or at infinity).
- The tangent to a field line at any point gives the direction of the electric field; in a uniform field, the lines are parallel and straight.
- No two electric field lines intersect, as this would imply more than one direction of the electric field at a point.
- Electric field lines do not pass through a conductor, showing that the electric field inside a conductor is zero.
- The density of field lines indicates field strength—closer lines represent a stronger field, while wider spacing represents a weaker field; the lines are continuous and imaginary, though the field is real.
Concepts [9]
- Historical Background of Electric Charges
- Basic Properties of Electric Charge
- Electric Lines of Force
- Electric Dipole and Its Properties
- Electrostatic Potential and Potential Energy
- Application of Gauss' Law
- Electrostatics of Conductors and Dielectrics
- Capacitors and Capacitance
- Distribution of Charges in a Conductor and Action at Points
