question_answer

Four cells of identical emf E and internal resistance r are connected is series to a variable resistor. The following graph shows the variation of terminal voltage of the combination with current. The emf of each cell used is

A)  \[1.4\,\,V\]             

B)   \[5.6\,\,V\]

C)  \[2\,\,V\]            

D)  \[1\,\,V\]