What happens to capacitive reactance as frequency increases?

What happens to capacitive reactance as frequency increases?

• A. It decreases
• B. It remains constant
• C. It increases
• D. It fluctuates

Answer: (A)

Capacitive reactance is defined by the formula \(X_c = \frac{1}{2\pi f C}\), where \(X_c\) is the capacitive reactance, \(f\) is the frequency of the AC signal, and \(C\) is the capacitance. From this formula, it is clear that as the frequency \(f\) increases, the value of \(X_c\) decreases. This inverse relationship means that higher frequencies result in lower capacitive reactance. This property of capacitive reactance is crucial in HVAC systems, particularly in circuits involving capacitors, as it affects how capacitors interact with other components like inductors, resistors, and the overall impedance of the circuit. When designing or troubleshooting HVAC control systems, understanding this relationship helps in predicting circuit behavior under varying operational conditions. Other choices represent behaviors that do not align with the established principles of electrical circuits. For example, constant, increasing, or fluctuating reactance does not accurately describe the predictable and inverse relationship between frequency and capacitive reactance.

Capacitive reactance is defined by the formula (X_c = \frac{1}{2\pi f C}), where (X_c) is the capacitive reactance, (f) is the frequency of the AC signal, and (C) is the capacitance. From this formula, it is clear that as the frequency (f) increases, the value of (X_c) decreases. This inverse relationship means that higher frequencies result in lower capacitive reactance.

This property of capacitive reactance is crucial in HVAC systems, particularly in circuits involving capacitors, as it affects how capacitors interact with other components like inductors, resistors, and the overall impedance of the circuit. When designing or troubleshooting HVAC control systems, understanding this relationship helps in predicting circuit behavior under varying operational conditions.

Other choices represent behaviors that do not align with the established principles of electrical circuits. For example, constant, increasing, or fluctuating reactance does not accurately describe the predictable and inverse relationship between frequency and capacitive reactance.