What is terminal potential differnce of a cell? Can its value be greater than the emf of a cell? Explian.

Options

A. being discharged
B. open circuit
C. being charged
D. being either changed or discharged

Answer

To answer the question, "What is the terminal potential difference of a cell? Can its value be greater than the EMF of a cell? Explain," we can break it down into several steps.

### Step-by-Step Solution:

**Step 1: Define EMF of a Cell**
- The electromotive force (EMF) of a cell, denoted as \( E \), is the maximum potential difference between the terminals of the cell when no current is flowing (open circuit condition). It represents the energy supplied by the cell per unit charge.

**Step 2: Define Terminal Potential Difference**
- The terminal potential difference (V) of a cell is the potential difference between the terminals of the cell when it is connected in a circuit and current is flowing. It can be calculated using the formula:
\[ V = E - I \cdot R \]
where \( I \) is the current flowing through the circuit and \( R \) is the internal resistance of the cell.

**Step 3: Analyze the Current Direction**
- If the current flows in the same direction as the EMF, the terminal voltage will be less than the EMF due to the voltage drop across the internal resistance. Thus, \( V < E \).

**Step 4: Consider Opposite Current Direction**
- If the current flows in the opposite direction to the EMF (for instance, when the cell is being charged), the terminal voltage can be expressed as:
\[ V = E + I \cdot R \]
In this case, the terminal voltage can be greater than the EMF, \( V > E \).

**Step 5: Conclusion**
- Therefore, the terminal potential difference of a cell can indeed be greater than the EMF of the cell when the current is flowing in the opposite direction to the EMF, indicating that the cell is being charged.