# Two cells of EMF 2E and E and internal resistance 2r and r respectively are connected in parallel. obtain the expression for equivalent EMF and the internal resistance of the combination

a) Eeff:-

E/r=E/r1+e/r2

b)Reff:-

1/r=1/r1+1/r2

using the above given relation u can solve ur query... :)

first let's find the equivalent internal resistance

1/r=1/2r+1/r=3/2r

---->

**r= 2r/3**

now for the equivalent emf

E/r=E1/r1+E2/r2

this implies E=r(E1/r1+E2/r2)

therefore, on substituting the values

E=2r/3(2E/2r+e/r)

=2r/3(2E/r)

=

**4E/3**

hope it helps.... :)