A battery of six cells each of e.m.f . 2V and internal resistance `0.5Omega` is being charged by D.C. mains of e.m.f. 220V by using an external resistance of `10Omega`. What is the potential difference across the battery?

Explanation

To solve the problem, we need to find the potential difference across the battery when it is being charged. We will follow these steps:

### Step 1: Determine the total EMF of the battery
The battery consists of 6 cells, each with an EMF of 2V. Therefore, the total EMF (E) of the battery can be calculated as:
\[ E = \text{Number of cells} \times \text{EMF of each cell} = 6 \times 2V = 12V \]

...