Question

In which of the following cases is the total emf of the cells in a circuit equal to the sum of the emf of all other cells used?
a)when cells are connected in series.
b) when cells are connected in parallel.
c)either a or b.
d)none of these.​

Answer 1

Answer:

connected in parallel

ok

Answer 2

Answer :

(a) When cells are connected in series.

Formula for the emfs in series is,

$\boxed {\large \rm{\xi_{eq} \: = \: \xi_{1} \: + \: \xi _{2} \: - - - - - \: + \: \xi _{n}}}$

And similarly formula of the internal resistance of emfs in series is,

$\boxed {\large \rm{r_{eq} \: = \: r_{1} \: + \: r _{2} \: - - - - - \: + \: r_{n}}}$