# what is the difference between ELECTROSTATIC POTENTIAL AND ELETRIC POTENTIAL ENERGY? towards which region will the electrons flow:towards region of higher potential or lower potential and why? Potentials are more positive in regions which are more positive, or less negative....why??

Ramesh V
70 Points
14 years ago

(a)

Electric Potential at a point is the amount of work done in bringing a unit positive charge from infinity to that point. ( Infinity refers to a very very large distance!)

Electric potential energy of a charge at a point is the work done in bringing that charge from infinity to that point.

Electric potential energy= charge x potential at that point.

The general expression for the electric potential as a result of a point charge Q can be obtained by referencing to a zero of potential at infinity. The expression for the potential difference is:

V = kQ/r

Electric Potential energy is defined as the capacity for doing work which arises from position or configuration. Here, a charge will exert a force on any other charge and potential energy arises from any collection of charges.

If a positive charge Q is fixed at some point in space, any other positive charge which is brought close to it will experience a repulsive force and will therefore have potential energy.

The potential energy of a test charge q in the vicinity of this source charge will be:

U = kQq/r         where k is coulombs constant

(b)

Electrons are negative charge carriers and they carry electrical charge in a metallic conductor. By convention, a current is supposed to flow from a higher potential to a lower potential point in the conductor. An electron source is always at a lower potential from where they flow to an electron sink which must be at a higher (+) potential. Hence the electron flow and current flow(positive charge) are in opposite directions.

(c)

The sign of the charge is important and can not be neglected when calculating the electric potential of a set of point charges.

A positive charge creates a positive potential around it in space while a negative charge creates a negative potential around it.

So,Potentials are more positive in regions which are more positive, or less negative.

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Regards,
Naga Ramesh
IIT Kgp - 2005 batch