All Flashcards
Describe the process of charging a capacitor in an RC circuit.
Initially, current flows freely into the uncharged capacitor. As the capacitor charges, the current decreases exponentially. Eventually, the capacitor reaches steady state, where its voltage equals the source voltage and current flow stops.
Describe the process of discharging a capacitor in an RC circuit.
When a charged capacitor discharges through a resistor, the charge, voltage, and current decrease exponentially with time. The rate of discharge is determined by the time constant τ = RC.
How do you calculate the total capacitance of capacitors connected in series?
Use the reciprocal formula:
How do you calculate the total capacitance of capacitors connected in parallel?
Add the capacitances directly:
What happens to a capacitor in a DC circuit over time?
Initially, current flows and the capacitor charges. As it charges, the current decreases. At steady state, the capacitor is fully charged, blocks DC current, and acts like an open circuit.
How do you find the total capacitance of capacitors in series?
Use the reciprocal addition formula:
How do you find the total capacitance of capacitors in parallel?
Add the capacitances directly:
Describe the process of charging a capacitor in an RC circuit.
Initially, current flows freely. As the capacitor charges, the voltage across it increases until it equals the source voltage, at which point current stops flowing.
Describe the process of discharging a capacitor in an RC circuit.
The capacitor releases its stored charge through the resistor, with the voltage and current decreasing exponentially over time.
What happens to the voltage across a capacitor in a DC circuit over time?
The voltage across the capacitor increases over time until it reaches the voltage of the source, after which it remains constant.
Define capacitance.
The ability of a component or circuit to collect and store energy in the form of an electrical charge.
Define steady state in a DC circuit with capacitors.
The condition where the capacitor is fully charged and no current flows through it, acting like an open switch.
Define time constant (τ) for an RC circuit.
τ = RC, the time it takes for a capacitor to charge to about 63% of its max voltage or discharge to about 37% of its initial voltage.
Define equivalent capacitance for capacitors in series.
The total capacitance of multiple capacitors in series, calculated using the reciprocal formula:
Define equivalent capacitance for capacitors in parallel.
The total capacitance of multiple capacitors in parallel, calculated by directly adding the individual capacitances: