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Electrical Engineering

Ohm's law states that, at constant temperature, the current through a conductor is:

Electrical power dissipated in a resistor can be expressed as:

A good electrical conductor is characterized by:

In a series circuit, which quantity remains the same through all elements?

In a parallel circuit, which quantity remains the same across all branches?

Star-delta (Y-Δ) conversion is primarily used to:

Kirchhoff's Current Law (KCL) is based on the principle of conservation of:

Kirchhoff's Voltage Law (KVL) is based on the principle of conservation of:

A circuit element whose V-I characteristic is a straight line through the origin is classified as:

A diode is an example of a:

The superposition theorem applies to circuits that are:

When applying superposition, an inactive voltage source is replaced by:

Thevenin's theorem replaces a linear two-terminal network with:

The Thevenin resistance Rᴛₕ is found by:

Norton's equivalent current source Iᴚ equals:

The relationship between the Thevenin and Norton equivalents is given by:

For maximum power transfer to a purely resistive load, the load resistance Rₗ must equal:

At the maximum power transfer condition (resistive case), the power transfer efficiency is:

For AC circuits with complex source impedance, maximum power transfer requires the load impedance to be:

Which theorem is NOT directly valid for computing power (as opposed to voltage/current) in a multi-source linear circuit?

An alternating EMF is generated in a coil primarily due to:

The instantaneous value of a sinusoidal voltage is expressed as v(t) =

The time period T of an alternating quantity is related to frequency f by:

For a pure sinusoidal waveform, the average value over a half-cycle equals:

The RMS value of a pure sinusoidal waveform equals:

The full-cycle average value of a pure sinusoidal AC quantity is:

Form factor of a sinusoidal waveform is defined as the ratio of:

Peak (crest) factor of a sinusoidal waveform is defined as the ratio of:

A 'cycle' of an alternating quantity refers to:

If the supply frequency is 50 Hz, the angular frequency ω is:

The transient response of a circuit refers to its behavior:

The time constant of an R-L circuit is given by:

The time constant of an R-C circuit is given by:

After one time constant, a first-order circuit's response has reached approximately what fraction of its total change?

A critically damped R-L-C circuit is characterized by:

An underdamped R-L-C circuit's response is characterized by:

An undamped R-L-C circuit (zero resistance, ideal) exhibits:

An overdamped R-L-C circuit's response reaches steady state:

The steady-state response of a circuit under sinusoidal AC excitation is:

A first-order transient is generally considered to have essentially decayed after approximately how many time constants?

Active (real) power in an AC circuit is given by:

Reactive power in an AC circuit is given by:

The relationship between apparent, active, and reactive power is:

A purely resistive load has a power factor of:

An inductive load typically has a power factor that is:

A low power factor for a given real power results in:

Power factor correction for an inductive (lagging) load is typically achieved by adding:

Series resonance in an R-L-C circuit occurs when:

At parallel resonance, the line current drawn from the source is:

The resonant frequency of a series or parallel R-L-C circuit is given by:

In a star-connected three-phase system, the line voltage relates to the phase voltage as:

In a delta-connected three-phase system, the line current relates to the phase current as:

A neutral conductor is available in which connection?

For a perfectly balanced three-phase load, the current in the neutral conductor is:

An unbalanced three-phase load causes:

Without a solidly connected neutral, an unbalanced star load can cause:

The total active power in a balanced three-phase system is given by:

The apparent power in a balanced three-phase system is given by:

In a delta connection, the phase voltage equals:

Which connection is typically preferred at the load end when both single-phase (line-to-neutral) and three-phase supply is required?

When a cylinder is unrolled (opened in rope form), what shape is formed?

How many transistors does a class B push-pull amplifier use?

In which region does a class B amplifier operate?

Which quantity remains constant (same) throughout a series circuit?

In a star (Y) connected three-phase system, what is the relationship between line voltage (Vₗ) and phase voltage (Vₚₕ)?

What is the primary advantage of CMOS logic technology?

What type of feedback do oscillators use to sustain oscillations?

Which theorem gives the condition for maximum power transfer from a source to a load?

According to Ohm's Law, which relationship is correct?

Three equal resistors in series dissipate 10 W. How much power do they dissipate when connected in parallel (same supply voltage)?

A semiconductor is primarily used for:

Two copper wires of the same length have cross-sectional area ratio 1 : 4. What is the ratio of their resistances (small : large)?

A wire has resistance 40 Ω. Another wire of the same length has 4× the cross-sectional area. What is the resistance of the second wire?

The Superposition Theorem is NOT applicable to which type of circuit analysis?

The current through a capacitor is known as:

A bridge rectifier operating at 50 Hz produces an output of:

An inductor and resistor are connected in series and a DC voltage V is applied. At steady state, what is the current?

Three resistors each of 2 Ω are connected in delta. What is the equivalent resistance between any two terminals?

A 1 Ω resistor is connected in parallel with a 3 Ω resistor. What is the equivalent resistance?

What is the Standing Wave Ratio (SWR) when the reflection coefficient is 0.8?

A transmission line has Z₀ = 50 Ω and termination impedance Za = 75 Ω. What is the SWR and reflection coefficient?

Flux linkage of a coil with N turns and flux Φ is given by:

The energy stored in the magnetic field of an inductor carrying current I is:

Ferromagnetic materials are characterized by:

Hysteresis loss in a magnetic material is represented by:

Retentivity of a magnetic material refers to:

Faraday's law of electromagnetic induction states that induced EMF is proportional to:

Lenz's law determines the:

A dynamically induced EMF (e=Blv) arises due to:

A statically induced EMF is best exemplified by:

The force on a current-carrying conductor in a magnetic field, F=BIl, is the basis of:

In a shell-type transformer, the core:

The conservator tank in a transformer is used to:

The breather in a transformer primarily functions to:

The open-circuit (no-load) test on a transformer is used to determine:

The short-circuit test on a transformer is used to determine:

Core (iron) loss in a transformer is essentially:

Maximum efficiency of a transformer occurs at the load where:

Eddy current loss in a transformer core is minimized by:

For successful parallel operation of two transformers, it is essential that they have:

Transformer capacity (rating) is expressed in:

The commutator in a DC machine primarily functions to:

A series DC motor is characterized by:

A shunt DC motor is characterized by:

Armature reaction in a DC machine refers to:

Sparking at the brushes due to armature reaction is commonly corrected using:

A starter is required when starting a DC motor mainly because:

Field control of a DC motor's speed operates by:

Armature (rheostatic) speed control of a DC motor gives speeds that are:

Maximum efficiency of a DC machine occurs when:

Which type of DC motor combines both series and shunt field windings?

In a synchronous machine, the field winding is typically excited by:

A salient-pole rotor construction is typically used for:

A brushless excitation system eliminates the need for:

The relationship between frequency, poles, and synchronous speed is given by:

The per-phase induced EMF equation for an alternator is given by:

Voltage regulation of an alternator is defined as the percentage change in terminal voltage when:

Before connecting (synchronizing) an alternator to the grid, which quantities must be matched?

For an alternator connected to an infinite bus, increasing the prime-mover's mechanical input primarily changes the machine's:

A synchronous motor, from standstill, develops:

An over-excited synchronous motor running unloaded, used for power factor correction, is called a:

A squirrel cage rotor is characterized by:

The rotating magnetic field in a three-phase induction motor is produced by:

Slip of an induction motor is defined as:

An induction motor can never run at exactly synchronous speed under load because:

Increasing rotor resistance in a slip-ring induction motor primarily: magnitude

Star-delta starting of an induction motor is used primarily to:

The blocked-rotor test on an induction motor is analogous to which transformer test?

The no-load test on an induction motor primarily determines:

The most widely used modern method for continuous, wide-range speed control of induction motors is:

Rotor resistance speed control is applicable to which type of induction motor?

A single-phase stator winding alone produces a magnetic field that is:

A single-phase induction motor, without any starting mechanism, has:

Once a single-phase induction motor is started (given an initial push), it continues to run because:

In a split-phase (resistance-start) motor, the auxiliary winding is designed with:

The auxiliary winding of a split-phase motor is typically disconnected once the motor reaches speed by:

A capacitor-start motor, compared to a plain split-phase motor, generally provides:

A shaded-pole motor achieves self-starting by:

Shaded-pole motors are typically used for:

Speed control of small single-phase induction motors (e.g. fans) is most commonly achieved by:

Which single-phase motor type generally provides the highest starting torque?

A Pelton wheel turbine is best suited for:

The Francis turbine is classified as a:

A Kaplan turbine is distinguished by:

The purpose of a surge tank in a hydro-plant layout is to:

A run-of-river hydro plant is characterized by:

The main function of a turbine governor is to:

Pumped storage hydro plants are primarily used for:

A penstock in a hydro-plant layout functions as:

Which turbine type is generally considered the most widely used worldwide, suited to a broad range of medium head/flow conditions?

A key site selection criterion for a hydroelectric power plant is:

A key advantage of diesel electric power plants is:

Diesel power plants are most commonly used for:

In a diesel plant, the governor primarily regulates:

The cooling system of a diesel engine primarily functions to:

The lubrication system in a diesel plant serves to:

In a diesel power plant, mechanical energy is converted to electrical energy by:

A key site selection factor specific to diesel power plants is:

Diesel engine starting systems commonly use:

Compared to hydroelectric plants, diesel plants generally have:

The exhaust system of a diesel engine is primarily responsible for:

Solar photovoltaic (PV) cells convert sunlight into electricity via:

An inverter in a solar PV system is used to:

Concentrated Solar Power (CSP) generates electricity by:

The function of a charge controller in an off-grid solar PV system is to:

Wind turbine power output is related to wind speed by:

A wind turbine converts kinetic energy of moving air into electricity via:

Pitch control in a wind turbine serves to:

A key operational challenge shared by both solar and wind power generation is:

Yaw control in a wind turbine primarily adjusts:

Compared to conventional thermal/hydro plants, solar PV plants typically have:

Pumped storage plants store energy by:

A key requirement for pumped storage plant siting is:

Battery Energy Storage Systems (BESS) are particularly valued for:

Compressed Air Energy Storage (CAES) typically requires:

Flywheel energy storage is best suited for:

Round-trip efficiency of an energy storage technology refers to:

Which storage technology generally offers the fastest response time?

For large-scale, long-duration grid energy storage, which technologies are generally most suitable?

Battery Energy Storage Systems store energy via:

A key advantage of battery storage over pumped storage is:

A brushless excitation system eliminates the need for:

A static excitation system derives field current from:

The primary function of an Automatic Voltage Regulator (AVR) is to:

An AVR operates as what type of control system?

Over-excitation limiting in an AVR primarily protects against:

Under-excitation limiting in an AVR primarily protects against:

Compared to DC excitation systems, static excitation systems generally offer:

In a DC excitation system, field current is supplied to the main generator via:

When generator load increases and terminal voltage tends to drop, the AVR responds by:

A key advantage of brushless excitation systems over slip-ring based systems is:

A key prerequisite before starting a hydro generator is:

A key prerequisite before starting a diesel generator is:

Before connecting a newly started generator to the grid, it must be:

A 'black start' refers to:

A black start unit is characterized by its ability to:

Why can't a typical large generating unit normally perform its own black start?

Common examples of black start units include:

The role of a black start unit during grid restoration is to:

Synchronizing a generator before grid connection is necessary to avoid:

For a diesel generator, the starting system prerequisite check specifically ensures:

A static error in measurement occurs when:

A systematic error is characterized by being:

Random (accidental) errors can best be reduced by:

A dynamic error arises specifically when:

The Maxwell (Maxwell-Wien) bridge is primarily used to measure:

A key advantage of the Maxwell bridge for measuring medium-Q inductors is that:

The Schering bridge is primarily used to measure:

The Wien bridge is notably used for:

At balance, the Wien bridge must simultaneously satisfy:

A gross error in measurement is typically caused by:

In a PMMC instrument, deflection is proportional to:

A moving iron instrument's deflection is proportional to:

An ammeter is connected in a circuit:

A voltmeter is connected in a circuit:

A wattmeter's deflection is proportional to:

A watt-hour (energy) meter differs from a wattmeter in that it measures:

A maximum demand meter is used to record:

The Kelvin double bridge is specifically designed for measuring:

A Megger (insulation resistance tester) is used to measure:

A galvanometer is primarily used as:

A potentiometer transducer produces an output that varies with:

An LVDT measures displacement by sensing:

The resistance of a strain gauge changes primarily due to:

A load cell typically uses which sensing element to measure force/weight?

The Hall Effect sensor generates a voltage that is:

A piezoelectric sensor generates an electrical output in response to:

A thermocouple generates a voltage based on which physical principle?

A key advantage of a thermocouple over a thermistor is:

A photoconductive cell (LDR)'s resistance:

A capacitive sensor detects changes based on variations in:

A weighted resistor D/A converter uses resistors that are:

A key drawback of the weighted resistor D/A converter is:

The R-2R ladder D/A converter's main advantage over the weighted resistor type is:

A dual-ramp (dual-slope) A/D converter determines the input voltage by:

A key advantage of the dual-ramp A/D converter is:

A successive approximation (SAR) A/D converter operates by:

Compared to the dual-ramp type, the successive approximation A/D converter generally offers:

Digital multimeters commonly use which A/D converter type, valuing accuracy over speed?

In an R-2R ladder D/A converter, the network structure primarily consists of:

The successive approximation A/D converter's internal comparator is used to:

A key advantage of digital instrumentation over analog instrumentation is:

A typical digital instrumentation system chain begins with:

GPIB (IEEE-488) is specifically designed for:

RS-232 is best described as:

Compared to RS-232, USB interfacing generally offers:

Ethernet/LAN interfacing for instruments primarily enables:

A microprocessor-based instrument can typically perform which additional function compared to a purely analog instrument?

Signal conditioning in a digital instrumentation chain typically includes:

A key benefit of microprocessor-based instrumentation is:

Which interface is a legacy but still-recognized standard specifically associated with connecting test and measurement instruments?

A Current Transformer's primary winding is connected:

A critical safety rule for Current Transformers is that the secondary must:

If a CT's secondary is accidentally left open while the primary carries current, the result is:

A measuring (metering) CT is specifically designed to:

A protection CT is specifically designed to:

The standard secondary current rating for most Current Transformers is:

A Potential Transformer's primary winding is connected:

A key safety consideration for Potential Transformers is that the secondary should never be:

The standard secondary voltage rating for most Potential Transformers is:

Compared to CTs, Potential Transformers are constructed essentially like:

An open-loop control system is characterized by:

A closed-loop (feedback) control system is characterized by:

A key disadvantage of open-loop systems compared to closed-loop systems is:

The transfer function of a linear system is defined as:

For a closed-loop system with forward gain G(s) and feedback gain H(s) (negative feedback), the overall transfer function is:

A key element unique to closed-loop systems (not present in open-loop systems) is the:

The error signal in a closed-loop system is generated by:

Which type of system generally provides better rejection of external disturbances?

A washing machine operating on a fixed timer (with no sensing of cleanliness) is an example of:

The transfer function concept applies strictly to systems that are:

A first-order system's step response is characterized by:

A second-order system with damping ratio ζ<1 is described as:

Critically damped response (ζ=1) is characterized by:

Settling time in a control system's step response refers to:

A linear control system is stable if and only if:

A pole located exactly on the imaginary axis of the s-plane indicates:

The Root Locus technique is used to study how a system's closed-loop poles move as:

In a PID controller, the proportional (P) term primarily:

The integral (I) term in a PID controller primarily serves to:

The derivative (D) term in a PID controller primarily:

A Bode plot represents a system's frequency response as:

Gain margin is measured at the frequency where:

Phase margin is measured at the frequency where:

For a stable control system, gain margin and phase margin should be:

A Nyquist plot is constructed by plotting:

The Nyquist stability criterion determines closed-loop stability by:

A key advantage of the Nyquist criterion over the Bode plot method is that it can:

The critical point used in Nyquist stability analysis is located at:

If the Nyquist plot passes very close to the critical point (−1+j0), the system is:

Both Bode and Nyquist plots are fundamentally used to analyze control systems in the:

A power diode is best described as:

A thyristor (SCR), once triggered on via its gate, will:

A GTO (Gate Turn-Off thyristor) differs from a standard SCR in that it:

A TRIAC is essentially equivalent to:

An IGBT combines characteristics of which two device types?

Compared to IGBTs, power MOSFETs generally offer:

Switching loss in a power semiconductor device occurs primarily due to:

Conduction loss in a power semiconductor device is primarily determined by:

A snubber circuit is used to:

Freewheeling (flyback) diodes are specifically used to protect switching devices when:

A half-wave rectifier conducts during:

A full-wave rectifier, compared to a half-wave rectifier, provides:

Total Harmonic Distortion (THD) quantifies:

Active power factor correction (PFC) circuits function by:

Pulse Width Modulation (PWM) in inverter control primarily serves to:

A basic square-wave inverter, compared to a PWM inverter, generally produces:

In a buck (step-down) DC-DC converter, the average output voltage is given by:

In a boost (step-up) DC-DC converter, the average output voltage is given by:

The average output voltage of a DC-DC converter is primarily controlled by adjusting:

A buck-boost converter is distinguished by its ability to:

An offline (standby) UPS normally supplies the load from:

An online (double-conversion) UPS provides power to the load via:

A line-interactive UPS differs from a basic offline UPS mainly by adding:

A key advantage of HVDC transmission over long-distance AC transmission is:

A monopolar HVDC link is characterized by:

A bipolar HVDC link offers improved reliability because:

A back-to-back HVDC link is specifically used to:

The smoothing reactor in an HVDC system primarily functions to:

DC filters in an HVDC system are used to:

The most critical and costly component of an HVDC transmission link is generally the:

An HRC (High Rupturing Capacity) fuse, compared to a rewireable fuse, offers:

A fuse's time-current characteristic is generally:

An isolator (disconnector) is characterized by:

The correct sequence for de-energizing a circuit using a circuit breaker and isolator is:

An isolator must never be operated:

A series (current-limiting) reactor is inserted into a power system to:

A shunt reactor is typically connected:

The Ferranti effect, which shunt reactors help mitigate, refers to:

A drop-out (expulsion) fuse is characterized by:

Common types of isolators used in outdoor substations include:

A vacuum circuit breaker (VCB) quenches the arc using:

A gas circuit breaker (GCB) typically uses which gas for arc quenching?

An oil circuit breaker (OCB) quenches the arc via:

The rated breaking capacity of a circuit breaker refers to:

The rated making capacity of a circuit breaker refers to:

A type test on a circuit breaker is:

An MCB (Miniature Circuit Breaker) is typically used for:

An MCCB (Moulded Case Circuit Breaker), compared to an MCB, generally offers:

Circuit breaker selection is primarily based on:

Operating (interrupting) time of a circuit breaker includes:

An IDMT (Inverse Definite Minimum Time) overcurrent relay is characterized by:

An earth fault relay is specifically designed to detect:

An undervoltage relay operates when:

A contactor differs from a circuit breaker in that a contactor:

Differential protection operates based on the principle that: internal fault

A key advantage of differential protection is:

Distance protection determines fault location by measuring:

Distance protection is most widely used for protecting:

Earth fault protection is generally more sensitive than phase-overcurrent protection because:

Overload protection, as distinct from short-circuit protection, typically involves:

A direct lightning stroke refers to:

An induced (indirect) lightning stroke affects a power line by:

A rod (spark) gap arrestor's main drawback is:

A horn gap arrestor improves on a simple rod gap by:

A valve-type lightning arrestor combines a series gap with:

A metal oxide (ZnO) lightning arrestor is distinguished by:

The core function of a lightning arrestor is to:

An overhead earth wire (shield wire) on a transmission line primarily functions to:

An overhead earth wire is positioned on a transmission tower:

After a metal oxide arrestor conducts a surge to ground, its behavior at normal system voltage is to:

A solidly earthed system's neutral is connected to earth:

A resistance earthed system limits ground fault current by: