Question

Two nonideal batteries are connected in parallel consider the following statements :-
(A) The equivalent emf is smaller than either of the two emfs
(B) The equivalent internal resistance is smaller than either of the two internal resistnaces

• A. both A and B are correct
• B. A is correct but B is wrong
• C. b is correct but A is wrong
• D. both A and B are wrong

Answer 1

The correct option is C b is correct but A is wrong

Consider the above figure showing two non idea batteries connected in parallel.

Emf of each of the batteries is $V_a-V_b=V_c-V_d$.

Equivalent Emf of the parallel combination=Potential difference across the end points $=V_a-V_b$

Hence equivalent Emf is equal to either of the two emfs.

But the resistances here are connected in parallel. Hence the equivalent resistance $=\frac{r}{2}$