What does a decrease in frequency do to the current in a capacitive circuit?

In a capacitive circuit, the relationship between frequency and current is governed by the properties of capacitors and their impedance. Capacitive reactance, which is the opposition that a capacitor offers to alternating current (AC), is inversely proportional to frequency. This relationship can be expressed with the formula for capacitive reactance (Xc):

[ X_c = \frac{1}{2\pi f C} ]

Where:

• ( X_c ) is the capacitive reactance,

• ( f ) is the frequency, and

• ( C ) is the capacitance.

As frequency decreases, the capacitive reactance increases. Since the impedance of a capacitive circuit is mainly determined by reactance, higher reactance leads to a reduction in the overall current flowing through the circuit. This is consistent with Ohm's Law, where current (I) is equal to voltage (V) divided by impedance (Z):

[ I = \frac{V}{Z} ]

With increased reactance at lower frequencies, the impedance rises, which in turn results in a decrease in the current. Therefore, in a capacitive circuit, a decrease in frequency leads to a decrease in current, making the given choice accurate.