Two cells of emf 10 V and 6 V, each having internal resistances of 2 Ω are connected in parallel across points A and B. The equivalent emf of the cells is

8 V

The correct answer is Option (2) → 8 V

$E_{\text{eq}} = \frac{\frac{E_1}{r_1} + \frac{E_2}{r_2}}{\frac{1}{r_1} + \frac{1}{r_2}}$

$E_{\text{eq}} = \frac{\frac{10}{2} + \frac{6}{2}}{\frac{1}{2} + \frac{1}{2}}$

$E_{\text{eq}} = \frac{5 + 3}{1}$

$E_{\text{eq}} = 8 \ \text{V}$

The equivalent emf is $8 \ \text{V}$.