Lecture on RC Circuits

These flashcards cover key concepts related to RC circuits, capacitors, and electrical principles discussed in the lecture.

What is the formula for the capacitance of a capacitor?

C = Ɛ * S / e, where S is the surface area of the plates and e is the thickness of the insulating material.

What is the energy stored in a capacitor?

Ec = 1/2 C Uc^2, where U_c is the voltage across the capacitor.

What is the breakdown voltage of a capacitor?

The smallest voltage that causes an electric spark between the plates, which can damage the capacitor.

What does the equation U_c(t) = E(1 - e^(-t/RC)) represent?

The voltage across a charging capacitor over time.

What does the time constant 'τ' in an RC circuit indicate?

The time required for the voltage or current to reach approximately 63% of its maximum value.

What happens to the charge on a capacitor when it discharges?

The charge decreases exponentially over time, described by the equation Q(t) = Q_0 * e^(-t/RC).

What is the relationship between voltage U, resistance R, and current I in an electric circuit?

According to Ohm's Law, U = RI.

What does the law of meshes in circuit analysis state?

The sum of voltage drops in a closed loop must equal the sum of voltage rises.

How do capacitors behave in series and parallel circuits?

In series, reciprocal of total capacitance equals the sum of reciprocals of individual capacitances. In parallel, total capacitance equals the sum of individual capacitances.

What factors affect the charging time of a capacitor in an RC circuit?

The resistance (R), capacitance (C), and the applied voltage (E) influence the charging time.