Circuit Analysis Final Exam Concept Review

What is Ohm's Law?

Ohm's Law states that V=IR, where V is voltage, I is current, and R is resistance.

What is the difference between a series and parallel circuit?

In a series circuit, components share the same current but different voltage drops. In a parallel circuit, components share the same voltage but different currents.

What is Kirchhoff's Voltage Law (KVL)?

KVL states that the sum of all voltages around a closed loop is zero.

What is Kirchhoff's Current Law (KCL)?

KCL states that the total current entering a node equals the total current leaving the node.

Define Thevenin’s Theorem.

Thevenin’s Theorem states that any linear circuit with resistors and sources can be reduced to a single voltage source in series with a resistor.

What is Norton’s Theorem?

Norton’s Theorem states that any linear circuit with resistors and sources can be reduced to a single current source in parallel with a resistor.

What is the relationship between Thevenin and Norton equivalents?

VTh=IN⋅RN and RTh=RN.

What is the purpose of a capacitor in a DC circuit?

A capacitor stores energy in an electric field and blocks DC after charging.

What is the impedance of a resistor, capacitor, and inductor?

Resistor: ZR=R; Capacitor: ZC=1/jωC; Inductor: ZL=jωL.

Define power in electrical circuits.

Power is the rate at which energy is transferred and is given by P=VI=I^2R=V^2/R.

What is the time constant in an RC circuit?

The time constant τ=RC.

How is the total resistance of resistors in series calculated?

Rtotal=R1+R2+⋯+Rn.

How is the total resistance of resistors in parallel calculated?

1/Rtotal=1/R1+1/R2+⋯+1/Rn.

What is mutual inductance?

Mutual inductance is the property where a change in current in one inductor induces a voltage in another nearby inductor.

What is the phase relationship between voltage and current in an inductor?

In an inductor, current lags voltage by 90°.

What is the phase relationship between voltage and current in a capacitor?

In a capacitor, current leads voltage by 90°.

What is a phasor?

A phasor is a complex number representing the magnitude and phase of a sinusoidal function in AC analysis.

What is the condition for maximum power transfer in a circuit?

Maximum power transfer occurs when the load resistance equals the Thevenin resistance of the source.

What is the unit of capacitance?

The unit of capacitance is the Farad (F).

What does the term 'steady-state' mean in circuit analysis?

Steady-state means that all transient behaviors have subsided, and the circuit variables are constant or sinusoidal.

How does an ideal voltage source behave?

An ideal voltage source maintains a constant voltage regardless of the current drawn.

How does an ideal current source behave?

An ideal current source maintains a constant current regardless of the voltage across it.

What is the purpose of a diode in a circuit?

A diode allows current to flow in one direction only, acting as a rectifier.

What is the difference between AC and DC?

AC is alternating current, which periodically reverses direction, while DC is direct current, which flows in one direction only.

What is the purpose of an operational amplifier (op-amp)?

An op-amp amplifies the difference between its two input voltages.

What is a node in a circuit?

A node is a point where two or more circuit elements are connected.

Define 'load resistance' in a circuit.

Load resistance is the resistance connected to the output of a circuit or device.

What is the resonant frequency of an RLC circuit?

The resonant frequency f0=1/(2π√(LC)).

What is the purpose of a transformer in AC circuits?

A transformer changes the voltage and current levels in AC circuits while maintaining the same power.

What is a short circuit?

A short circuit occurs when a low-resistance path bypasses the intended load, causing excessive current flow.

What is the unit of inductance?

The unit of inductance is the Henry (H).

What is the cutoff frequency in an RC filter?

The cutoff frequency fc=1/(2πRC).

What is the purpose of a capacitor in an AC circuit?

A capacitor filters signals, blocks DC, or creates phase shifts.

What happens to current in an open circuit?

In an open circuit, current flow is zero.

What is a supernode?

A supernode is formed when a voltage source connects two nodes, and KCL is applied to the combined node.

What does 'ground' mean in a circuit?

Ground is the reference point for voltage in a circuit, usually considered 0V.

Define reactance.

Reactance is the opposition to AC current by capacitors or inductors.

What is a mesh in a circuit?

A mesh is a loop in a circuit that does not contain any other loops within it.

What is the unit of resistance?

The unit of resistance is the Ohm (Ω).

What is a transient response in a circuit?

A transient response is the temporary behavior of a circuit as it transitions from one state to another before reaching steady-state.