*Question G5A06:
How does a capacitor react to AC?*  

*Correct Answer is  A: As the frequency of the applied AC increases, the reactance decreases*  

### AI Response: (may contain errors)  

A capacitor's reactance to AC is determined by its capacitive reactance, which is given by the formula:

$$X_C = \frac{1}{2 \pi f C}$$

where:
- $X_C$ = capacitive reactance in ohms
- $f$ = frequency of the applied AC in hertz
- $C$ = capacitance in farads

### Explanation:

1. **Correct Answer (A):**  
   As the frequency ($f$) of the applied AC increases, the denominator of the formula ($2 \pi f C$) becomes larger, which makes the capacitive reactance ($X_C$) smaller. Therefore, the reactance decreases with increasing frequency.

2. **Why Other Choices Are Incorrect:**
   - **Choice B:** This is incorrect because it states the opposite of what actually happens. As frequency increases, reactance decreases, not increases.
   - **Choice C:** The amplitude of the AC signal does not affect the reactance. Reactance is dependent on frequency and capacitance, not amplitude.
   - **Choice D:** Similar to Choice C, the amplitude of the AC signal does not influence the reactance, so this statement is incorrect.

### Key Points:
- Capacitive reactance is inversely proportional to frequency.
- Amplitude of the AC signal does not affect capacitive reactance.