Introduction to Capacitors and Circuits

These flashcards cover key concepts and terminology related to the behavior of capacitors and RC circuits discussed in the lecture notes.

What percentage of a capacitor's total charge is accumulated after one time constant during charging?

63% of its total charge.

What happens to the current in a capacitor as it charges over time?

The current starts at its maximum value and decays exponentially to zero.

How is the time constant (τ) calculated in a resistor-capacitor (RC) circuit?

τ = R × C, where R is the resistance and C is the capacitance.

What does a capacitor behave like at short times after a switch is thrown?

An ideal wire.

At long times, what does a fully charged capacitor act like?

An open circuit.

In an RC circuit, what is the relationship between voltage (V), charge (Q), and capacitance (C)?

Q = C × V.

What is the effect on total resistance when resistors are added in parallel?

The overall resistance decreases.

What is the significance of the maximum current I₀ in an RC circuit?

It is the current at time t = 0 when a capacitor is freshly charged.

What factors determine the final charge on a capacitor?

The capacitance and the voltage applied across it.

How does the potential at the center of a charged arc change when comparing a quarter arc to a three-quarter arc?

The potential differs due to the distribution of charge along the arcs.

What does power depend on in an electrical circuit?

Power depends on current and voltage, specifically P = IV.

What mathematical operation is used to find energy from power over time?

Integration of power with respect to time.

What does it mean for the current in a circuit to be transient?

It means the current changes over time, typically during charge or discharge phases.

In what scenario does a capacitor start acting like an open circuit?

When it is fully charged.