In which case is the junction diode is not reverse bias-

Options

A.
B.
C.
D.

Answer

To determine in which case a junction diode is not reverse biased, we need to analyze the conditions of biasing in a PN junction diode.

### Step-by-Step Solution:

1. **Understanding Diode Biasing**:
- A junction diode consists of a P-type and an N-type semiconductor.
- When the diode is forward biased, the P-side (anode) is connected to a higher potential than the N-side (cathode).
- Conversely, when the diode is reverse biased, the P-side is at a lower potential than the N-side.

2. **Identifying the Conditions**:
- We need to evaluate the given options (A, B, C, D) to find out which scenario does not reverse bias the diode.
- The condition for forward bias can be stated as:
\[ V_A > V_B \]
- Where \( V_A \) is the voltage at the anode and \( V_B \) is the voltage at the cathode.

3. **Analyzing Each Option**:
- **Option A**: If \( V_A = 5V \) and \( V_B = 10V \):
- Here, \( 5V < 10V \) (reverse biased).
- **Option B**: If \( V_A = -10V \) and \( V_B = -15V \):
- Here, \( -10V > -15V \) (forward biased).
- **Option C**: If \( V_A = 0V \) and \( V_B = 5V \):
- Here, \( 0V < 5V \) (reverse biased).
- **Option D**: If \( V_A = 3V \) and \( V_B = 3V \):
- Here, \( 3V = 3V \) (neither forward nor reverse biased).

4. **Conclusion**:
- From the analysis, we find that **Option B** is the only case where the diode is not reverse biased, as it is forward biased.
- Therefore, the answer to the question is **Option B**.