What is electric potential , potential difference , e.m.f .. ?

Question

Can anyone tell me what electric potential , potential difference , e.m.f is? Also how do the charges in a metal flow when they are connected to a battery ?

Answer 1

V=E-Ir where E is emf, I is current and r is internal resistance of the cell.

V=E only when no current passes through the cell or when external resistance is infinite..

Answer 2

My friend eletric potential is the capacity of eletric field to do the electrical work per unite charge OR electrical work done per unit charge due to presence of eletrical field is known as eletrical potential.This is the defination of Electric Potential.

   dV= -w/dq          ( V = eletric field)

                            ( w = eletrical work done by the eletrical field)

                            ( q = the eletric charge)

Potential diffrence:- work done in moving a unite positive charge from one point to another point aginst the electric field.

                     infinity

                   ,/'      = dq/dw         here,dq = unite positive charge

                   0                                   dw = work done by unit positive

                                                                 charge

e.m.f of a battery:-the work done by an non eletrical force to move unit positive charge from one end to another end is known as e.m.f.     (here non eletrical force means chemical reaction )

              V=E - Ir  where v = volt

                                     e = eletric force

                                     I = eletric current

                                   &r = internal resistance

              .'. V=e       when no current passes from the battery bcoz at that time internal resistance is infinate i.e zero so I will also b zero bcoz multiplied by 'r'.

Answer 3

electric potential is the energy produced from electric battery, potential difference is the energy produced from a circuit, and emf is the energy that is used as a external energy to produce potential difference in a circuit

as you know electrons are the carriers of charges in metal, the electrons move in the opposite direction to that of the field, in other words the charge opposite to the flow of the field is so called electrons which carry charges, they carry negative charges

Answer 4

electric potential - The workdone in moving a unit positive charge from infinity to that point is called electric potential.

potential difference - The workdone in moving a unit positive charge from one point to another is called potential difference.

             V=Q/T

Answer 5

ELECTRIC POTENTIAL: it is the amount of work done in moving a unit positive charge from infinity to a point against the electric forces.

POTENTIAL DIFFERENCE: is the amount of work done in moving a unit positive charge from one point to another against the electric forces.

EMF or electromotive force is the external energy necessary to drive the free electrons in a definite direction.

When connected to a battery, the electrons in the metal experience a force in a direction opposite to the electric field and they get drifted towards the positive terminal.

Answer 6

Electric potential is a measure of the capacity of an electric field to do work, per unit charge (dV = -W/dq)

It can be analagous to the potential of an object high in a gravitational field, as it will tend to a lower point, so does electric charge, it will travel from high to low potential (conventional current, electrons actually travel the opposite way). This difference of potential is potential difference, or Voltage.

EMF or electro motive force, is the force responsible for moving charge through a circuit (providing current), and is the maximum potential difference across a circuit (i.e when it is not closed, is equal to terminal voltage), when a circuit is closed, emf drops due to terminal resistance of EMF source (battery etc)

Charges flow by the motion of free electrons within the metal

Answer 7

electric potential  due to point charge is the amount of work done to move a unit positive charge from infinity to that point in the electric field.

potential difference is the difference between the potential of two electrodes of a cell when it is in the closed circuit.

emf is the total potential difference of a cell in an open circuit.

Charge carriers in the metal are electrons. Therefore charge moves in the opposite direction to the flow of current in the metal.