Which of the junction diodes shown below are forward biased ?

Options

A.
B.
C.
D.

Explanation

To determine which of the junction diodes are forward biased, we need to understand the basic principle of how a p-n junction diode operates under forward bias conditions.

### Step-by-Step Solution:

1. **Understanding Diode Structure**:
- A p-n junction diode consists of two regions: p-type (positive) and n-type (negative).
- The p-type region is doped with acceptor impurities, while the n-type region is doped with donor impurities.

**Hint**: Remember that the p-type region has an abundance of holes (positive charge carriers), while the n-type region has an abundance of electrons (negative charge carriers).

2. **Forward Bias Condition**:
- For a diode to be in forward bias, the p-type side must be connected to a higher potential (positive terminal) and the n-type side must be connected to a lower potential (negative terminal).
- This reduces the width of the depletion region and allows current to flow through the diode.

**Hint**: Visualize the connection: p-type to positive voltage and n-type to negative voltage.

3. **Analyzing Given Options**:
- Examine the voltage connections for each diode shown in the options.
- Identify which diode has the p-type connected to a higher voltage than the n-type.

4. **Evaluating Each Option**:
- **Option A**: p-type connected to -5V and n-type connected to -10V. Here, p-type is at a higher potential than n-type, indicating forward bias.
- **Option B**: p-type connected to 0V and n-type connected to -5V. The p-type is at a higher potential than n-type, indicating forward bias.
- **Option C**: p-type connected to -5V and n-type connected to 0V. The p-type is at a lower potential than n-type, indicating reverse bias.
- **Option D**: p-type connected to -10V and n-type connected to -5V. The p-type is at a lower potential than n-type, indicating reverse bias.

**Hint**: Compare the voltage levels for each option to determine which configuration meets the forward bias criteria.

5. **Conclusion**:
- Based on the analysis, **Options A and B** are forward biased, while **Options C and D** are reverse biased.

### Final Answer:
- The junction diodes that are forward biased are **Option A and Option B**.