Ohm’s Law states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance. This is expressed as V = IR.
In a series circuit, the current is?
A Constant
B Variable
C Zero
D Split
In a series circuit, the current remains the same throughout the circuit. This is because there is only one path for the current to flow, so the same current must pass through each component.
What is the main purpose of Thevenin’s Theorem?
A Reduce voltage
B Increase power
C Measure current
D Simplify circuits
Thevenin’s Theorem simplifies a complex circuit to a single voltage source in series with a resistance, making analysis of the circuit easier, especially when finding the current or voltage across a load.
What is impedance in AC circuits?
A Current flow
B Total opposition
C Resistance
D Voltage rise
Impedance is the total opposition that a circuit offers to the flow of alternating current. It is a combination of resistance and reactance (capacitive and inductive reactance) and is measured in ohms.
Which theorem helps calculate current through multiple sources?
A Thevenin
B Nodal analysis
C Superposition
D Maximum power transfer
The Superposition Theorem states that in a linear circuit with multiple sources, the current or voltage in any component can be found by considering each source individually, turning off others, and summing the results.
What does a phasor represent in AC circuits?
A Sinusoidal wave
B Voltage
C Power
D Current
A phasor is a complex number representation of a sinusoidal function. It simplifies AC analysis by converting time–varying signals into a constant value, representing both amplitude and phase of the wave.
What is the unit of reactance?
A Watt
B Ampere
C Ohm
D Volt
Reactance is the opposition to the change in current flow in an AC circuit and is measured in ohms, just like resistance. It can be inductive or capacitive, affecting how AC signals behave in a circuit.
In resonance, what happens to impedance in a series RLC circuit?
A Zero
B Infinite
C Maximum
D Minimum
At resonance in a series RLC circuit, the inductive and capacitive reactances cancel each other out. This results in the total impedance being at a minimum, which allows maximum current to flow through the circuit.
Which circuit component stores energy in an electric field?
A Capacitor
B Inductor
C Diode
D Resistor
A capacitor stores electrical energy in an electric field between its plates. When connected to a power source, it charges up, and when the source is disconnected, it can release the stored energy.
What does the maximum power transfer theorem state?
A Voltage should be doubled
B Power loss is minimized
C Maximum power is delivered to load when resistance matches
D Impedance should be zero
The Maximum Power Transfer Theorem states that maximum power is delivered to a load when the load resistance equals the source resistance. If the load resistance is greater or less, the power delivered decreases.
What does mesh analysis primarily solve for?
A Resistance
B Current
C Impedance
D Voltage
Mesh analysis is a method used to find the current in each mesh (loop) of a circuit. By applying Kirchhoff’s Voltage Law (KVL) to each loop, the currents can be determined.
What is the primary function of an inductor?
A Store energy in a magnetic field
B Limit current flow
C Control voltage
D Store energy in an electric field
An inductor stores energy in the form of a magnetic field when current flows through it. It resists changes in current, making it useful for filtering and energy storage in circuits.
In an AC circuit, what does the power factor represent?
A Current efficiency
B Voltage ratio
C Resistance ratio
D Efficiency of power transfer
The power factor in an AC circuit is the ratio of real power to apparent power. It indicates the efficiency with which power is being used, with a power factor of 1 (or 100%) representing perfect efficiency.
What is the steady-state response of a circuit?
A The transient behavior
B The voltage change
C The behavior after a long time
D The initial current
The steady-state response refers to the behavior of a circuit after a long time when all transient effects have settled, and the system has reached a stable condition under constant inputs.
What does Norton’s Theorem help simplify?
A Resistance calculation
B Complex circuits
C Current sources
D Voltage source
Norton’s Theorem simplifies a complex linear circuit into a simple equivalent circuit with a current source in parallel with a resistance. This helps in easier analysis of circuits with multiple sources.