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-let battery voltage=10v and 0 internal resistance

-let R=5 ohms

KEY

e- negative charge

e+ positive charge

+ve positive

-ve negative

U potential energy

K kinetic energy

E total energy

now we will discuss the circuit in terms of electrons:

_____A BRIEF DIGRESSION HERE____

-there is a "BATTERY FORCE"(due to chemical reactions),F1 (SAY), that moves an e- from +ve terminal to -ve terminal WHEN the battery is connected to a circuit.

-HENCE THE DIRECTION OF F1,WHISCH ACTS ON AN e-,IS DOWNWARDS

-there is an electric field due to oppositely charged plates of the cell.this field causes an e- to experience a force F2 (say).

-F2 ACTS UPWARDS

-IN EQUILIBRIUM,i.e. WHEN the cell is'nt connected to a circuit,F1=F2.no

movement of charge occurs.

-the battery has set up an electric field in the wire.

-an e- NEAR THE + TERMINAL enters the cell/battery.

-it TENDS to reduce the potential of the +terminal.hence F2 decreases

-now the "battery force" F1 becomes dominant and moves an e- from + terminal to - terminal by doing WORK ON THE e-

-the e- has been moved to a position where its U=10e=U1,LET

-now it is accelerated by the electric field and E=U1+K(x),where k is a function of distance x.

__________CONSIDER THE TWO CASES THAT ARISE_______

---A--- R=0

---B--- R>0

---A--- if R=0,

THEN the e- goes to the + terminal of the cell.its energy profile is as follows:

U=0 (i am a little doubtful about this)

K=k

-the e- will be accelerated indefinitely when R=0

---B--- R>0

-the e- encounters a resistance,its U=U1 will decrease and K will EFFECTIVELY be a constant,say k (remember,that drift velocity is a constant in such cases) .of course the instantaneous values of K may differ from k.

K averages to k because electric field tries to increase K but collisions with the ions in metal decreases K.

-so it is the U1 and the changes in K from k which cause heating of the resistor.

-power(P)=I^2 * R...right.

-hence

P=f(U) for a circuit with a give resistance...

the above equation seems quite reasonable because.U AND R decide the current and the K...

CONCLUSIONS:

1.POTENTIAL DROP OCCURS ONLY WHEN R>0

2.e- ARE ACCELERATED INDEFINITELY IN A SHORT (POWER DISSIPATED WILL BE HIGH BUT NOT INFINITE...THE SHORT SIMPLY MELTS)

NOW...A FEW DOUBTS

IS THE POTENTIAL IN A CURRENT CARRING CONDUCTOR(R=0) CONSTANT AND

NON-ZERO.(IF YES THEN MY ABOVE EXPLANATIONS SEEM TO BE OKAY)

HONESTLY IAM MYSELF NOT CONVINCED ABOUT MY EXPLANATIONS,ESPECIALLY ABOUT POTENTIAL ENERGY...ANYWAY THANKS FOR READING PATIENTLY...