## Electric Current

Electric Current is the rate of flow of charge through a particular cross sectional area with respect to time. Units for current is ampere (A) 1 A = 1 $C \, S^{-1}$ $$I = \frac{Q}{t}$$ , where I = current, Q = charge, t = time Instantaneous Current $$I = \frac{dQ}{dt}$$ The charge that passes through a given point is …

## Electric Potential Energy

Electric potential energy of a charge in an electric field is defined as the work done by an external force in bringing the charge from infinity to that point a distance r away. $U = \frac{Q_{1} Q_{2}}{4 \pi \epsilon_{o} r}$ , where U is electric potential energy, Q is charge, r is distance between the two charges, $\epsilon_{o}$ is the permittivity …

## Equipotential Line

An equipotential line is a line joining points having the same potential. If an object is moved from one point on a line of equipotential to another point on the same line, there is no change in its potential. Hence, no work is done. Equipotential Lines are always perpendicular to electric field lines. Distance between lines for equal increment of …

## Electric Potential

Electric Potential at a point in an electric field is the work done per unit charge by an external agent in bringing a positive test charge from infinity to that particular point without acceleration. E-field lines always point from region of high potential(+) to regions of low potential (-) Unit: Volts (V) Various equations for electric potential: $$V = \frac{W}{q}$$ …

## Acceleration Due To Electric field

When a charged particle is placed in an uniform electric field, in absence of all other forces, it will experience an acceleration in the direction of the field lines. $F = ma$ $qE = ma$ $a = \frac{qE}{m}$ All laws of Kinematics can be applied to the motion of the charged particle.

## Drawing Field Lines

The electric field lines are parallel to the direction of force experienced by a positive test charge placed at that point. Basic conventions when drawing field lines Field lines extend out from positive charges Field lines go into negative charges All field lines are continuous curves or lines without breaks Field lines never cross each other’s path Field lines in …

## Coulomb’s Law

The coulomb’s law states that the electrostatic force between two point charges is proportional to the product of their charges and inversely proportional to the square of the distance between them. $F = \frac{Q_{1} Q_{2}}{4 \pi \epsilon_{o} r^{2}}$ , where Q is charge, r is the distance between the two charge, $\epsilon_{o}$ is the permittivity of free space Like charges, repulsion …