Potential
-
Upload
rajaganapathi-rajappan -
Category
Documents
-
view
3 -
download
1
description
Transcript of Potential
Potential
Potential
Potential DifferenceThe potential difference between the points A and B is defined as the work done to move a unit charge from point A to point B
Work done( ) to move the charge for small distance :
Work done = Force x DistanceTotal Work done (W) to move the charge from A to B:
Work done to move unit charge from A to B is potential difference between A and B
We know that
..1
- a charge which create the electric field E
- Potential at a point A- Potential at a point B
Eqn2 ,Eqn.3 in Eqn.1
From Fig.1
.3;
..2
Potential Difference
The potential difference between the points A and B is defined as the work done to move the unit charge from A to B
Work done to move the charge for small distance
Work done = Force x DistanceTotal Work done to move the charge from A to B
- Potential at a point A- Potential at a point BVoltWork done to move unit charge from A to B is potential difference between A and B
Potential or Absolute PotentialPotential at any point is defined as the work done to move a unit positive charge from infinite to a that point in an electric field (E)
Potential difference between a point A and B:
...1To find potential (V) at point B substitute in Eqn. 1
- a charge which create the electric field E
Total change (dv )in V(x,y,z) is the sum of partial changes ( ) with respect to x,y,z.
Relation between Electric field and potential (E and V)We know that. 1. 2Compare 1 and 2
Electric Dipole The two equal and opposite charges ,which are separated by a small distance, is called electric -dipole or dipole.Dipole Moment(M)It is defined as the product of charge(Q) and distance (d)between the charges
Potential and Electric field intensity due to an electric dipoleConsider a positive and negative point charges separated by a distance d.Position of the charges and are (0,0,d/2) and (0,0,-d/2) respectively.The potential at point P is the sum of potential due to individual charges at that point
- distance between charge and point P- distance between charge and point P
If the point is far away from the charges the difference between and is negligible.
This approximation may not be made in the numerator
In spherical co-ordinate system
We know that14Eqn.2 ,Eqn.3 in Eqn.1235
6
7
8
9Eqn.7,Eqn.8,Eqn.9 in Eqn.6