Which statement best describes the behavior of a capacitor in DC circuits according to the material?

• A. Capacitors cannot be used in DC circuits.
• B. The capacitor will charge to the source voltage and then act as an open in the circuit.
• C. The capacitor will charge to the source voltage and then act as a short in the circuit.
• D. The capacitor will discharge until voltage is removed then act as an open.

Answer: (B)

In DC circuits, a capacitor’s steady-state behavior is to block current once it is charged. When the capacitor is connected to a DC source, it charges up toward the source voltage. As the charge builds, the current tapers off until the capacitor’s voltage equals the source voltage and the current goes to zero. With no current flowing in steady state, the capacitor behaves like an open circuit, effectively isolating the portion of the circuit beyond it. That’s why the statement that best describes its DC behavior is that it will charge to the source voltage and then act as an open in the circuit.

Capacitors can still be used in DC applications for tasks like coupling or filtering, so they do have a place in DC circuits; they just don’t pass steady DC after they’re charged. They do not act as a short after charging, and they don’t inherently discharge to remove voltage without a discharge path.