What does transient response describe in a circuit?
A Frequency behavior
B Steady-state behavior
C Initial change after disturbance
D Long-term stability
Transient response refers to the behavior of a circuit immediately following a disturbance, such as turning a switch on or off. It involves the temporary changes in voltage and current until the circuit reaches steady-state.
In an AC circuit, what does impedance represent?
A Only reactance
B Total opposition to current
C Voltage across the circuit
D Resistance only
Impedance is the total opposition a circuit offers to the flow of alternating current (AC). It combines both resistance and reactance (inductive and capacitive), and is measured in ohms, affecting both current and voltage in AC circuits.
How does resonance occur in an RLC circuit?
A Inductive and capacitive reactances cancel out
B Impedance becomes infinite
C Voltage decreases
D Current decreases
Resonance in an RLC circuit occurs when the inductive reactance and capacitive reactance cancel each other out, resulting in minimum impedance. This allows the maximum current to flow through the circuit at the resonant frequency.
What does the power factor indicate in an AC circuit?
A Resistance value
B Voltage regulation
C Efficiency of power usage
D Current flow
The power factor indicates how efficiently electrical power is being used in an AC circuit. A power factor of 1 (or 100%) represents perfect efficiency, where all the supplied power is used effectively for work.
What is the primary purpose of the Laplace transform in circuit analysis?
A Simplify impedance calculations
B Convert time-domain signals to frequency-domain
C Solve differential equations
D Calculate power loss
The Laplace transform is used in circuit analysis to convert time-domain signals (like voltages or currents) into the frequency domain, simplifying the process of solving circuits with reactive components and transient behavior.
In a parallel RLC circuit, what happens at resonance?
A Current is minimized
B Voltage becomes zero
C Power is dissipated
D Impedance is minimized
At resonance in a parallel RLC circuit, the impedance is minimized. The inductive and capacitive reactances cancel each other out, allowing maximum current to flow through the circuit at the resonant frequency.
What does the transient response of a series RLC circuit depend on?
A Initial conditions
B Source voltage
C Frequency
D Impedance
The transient response of a series RLC circuit depends on the initial conditions, such as the initial voltage across the capacitor and the initial current through the inductor. These conditions determine how the circuit will respond after a disturbance.
How is current divided in a parallel circuit according to the current division rule?
A Equal among branches
B Inversely proportional to resistance
C Proportional to voltage
D Proportional to resistance
In a parallel circuit, current divides inversely proportional to the resistance of each branch. The branch with a higher resistance will have less current flowing through it, while the branch with lower resistance will have more current.
What is the role of a signal flow graph in circuit analysis?
A Determine resonance frequency
B Find current division
C Represent circuit equations
D Calculate power factor
A signal flow graph is used to represent the equations governing a system or circuit, helping visualize the relationship between various circuit parameters. It is especially useful in system dynamics and circuit optimization.
In an AC circuit, what is reactance?
A Total opposition to current
B Power dissipation
C Opposition to change in current
D Opposition to DC
Reactance is the opposition to changes in current, caused by inductors and capacitors in an AC circuit. It depends on the frequency of the AC signal and is measured in ohms, affecting the amplitude and phase of the current.
How does frequency affect the impedance of a series RLC circuit?
A Increases with frequency
B Remains constant
C Decreases with frequency
D Becomes zero
In a series RLC circuit, the impedance increases with frequency, as the inductive reactance increases. At resonance, the impedance is at its minimum. Outside resonance, the impedance increases, especially if the circuit is more inductive.
What does the term “steady-state response” refer to in an AC circuit?
A Transient current
B Initial current behavior
C Final, stable state
D Resistance to AC
The steady-state response refers to the behavior of a circuit after all transient effects have settled. In AC circuits, it is the behavior when the system reaches a stable, repeating pattern, typically described by sinusoidal functions.
What is the result of adding more resistors in parallel?
A Increases voltage drop
B Decreases current
C Decreases total resistance
D Increases total resistance
In a parallel circuit, adding more resistors decreases the total resistance. This is because the total resistance is the reciprocal of the sum of the reciprocals of individual resistances, leading to a lower overall resistance.
What does resonance in an RLC circuit result in?
A Zero voltage
B Minimum current
C Maximum power loss
D Maximum current
At resonance in an RLC circuit, the impedance is minimized, allowing the maximum current to flow. This is because the inductive and capacitive reactances cancel each other out, resulting in a purely resistive circuit.
What is the impedance of a purely inductive AC circuit?
A Zero
B Capacitive reactance
C Inductive reactance
D Resistance
The impedance of a purely inductive AC circuit is purely inductive reactance, which is given by XL = 2πfL, where f is the frequency and L is the inductance. This opposes changes in current and causes a phase shift of 90°.