Sir see the formulae where I circle h ere I can t understand how they com e and by which concept Please please please simple way mail bta dijiye sir And tell me in question how can I de termine that the question is of chargi ng or discharging Board Competitive Exams Level 30 Current Electricity When the resistance R is infinite or P and N are in open circuit there is no current through the electrolyt 1 2 0 Potential difference between P and N V Vp VA VA VB VB VN V 0 V V V E A cell can be represented as PN emfe of a cell is defined as the potential difference between the positive and negative electrodes in an ope circuit When R is finite 0 Cell is discharging Potential difference between P and N is V Vp VA VA VB VB VN V Ir V V V Ir e Ir V t Ir We can represent it as P Internal resistance of the cells in the circuit may be neglected when the current is such that Ir Internal resistances of dry cells is much higher than common electrolytic cells Note In case of storage cells discharged cells can by charged by a driver cell E by supplying a steady current I through the cell from P to N as shown in figure In this case potential difference between P and N is V V V VA VB VB VN A V Ir V V V Ir Ir V 8 Ir P It can be represented as P P www N Potential difference between terminals of cell may be equal to greater than or less than the emf of cell V E 1 a If current shown from cell is zero i 0 b Cell is ideal r 0 Potential difference between P and N can be written as V IR Equation 29 can be written as IR E Ir So V E R r E ER R r 3 29 P A E N B 30 Board Exam Solu ZEM P Ex S