Question

Four identical cells each having emf E and r are connected in series to form a loop ABCD .find potential difference across AB and AC

Answer 1

Answer:

Four identical cells each having emf E and r are connected in series to form a loop ABCD .

Explanation:

The net emf of circuit is 2E because two cells are joined with same polarity and two withdifferent

Current=net emf/net resistance

         =2E/4r

        =E/2r

Potential difference across AB=E−Ir

                                                =E−E/2r×r

                                                =E/2

Hence the potential difference across AC= 0−I×2r

                                                        = −E/2r×2r

                                                                  =−E