Question

how to find the emf
help ​

Answer 1

As an example, imagine you have a circuit with a potential difference of 3.2 V, with a current of 0.6 A flowing and the internal resistance of the battery at 0.5 ohms. Using the formula above:

ε = V + Ir

= 3.2 V + 0.6 A × 0.5 Ω

= 3.2 V + 0.3 V = 3.5 V

So the EMF of this circuit is 3.5 V.