*Question E5B02:
What letter is commonly used to represent susceptance?*  

*Correct Answer is  D: B*  

### AI Response: (may contain errors)  

The correct answer to the question about the letter commonly used to represent susceptance is **C: Y**.

### Explanation:

1. **Why the correct answer is correct:**
   - **Susceptance** is a measure of how easily a circuit allows alternating current (AC) to flow due to reactive components (inductors and capacitors). It is the reciprocal of reactance and is represented by the letter **Y** in electrical engineering. The relationship can be expressed as:
     $$
     Y = \frac{1}{X}
     $$
   where $Y$ is the susceptance and $X$ is the reactance.

2. **Why the other choices are incorrect:**
   - **A: G** - This letter represents **conductance**, which is the reciprocal of resistance. It is not used for susceptance.
   - **B: X** - This letter represents **reactance**, which is the opposition to AC due to inductance or capacitance. It is not the same as susceptance.
   - **D: B** - This letter is often used to represent **magnetizing inductance** or **reactance** in some contexts, but it is not the standard notation for susceptance.

### Useful Formulas:
- The relationship between impedance ($Z$), admittance ($Y$), resistance ($R$), and reactance ($X$) can be summarized as:
  $$
  Y = G + jB
  $$
  where:
  - $G$ = conductance (real part)
  - $B$ = susceptance (imaginary part)

This helps clarify the distinction between these terms and their respective symbols in circuit analysis.