Technical practice questions
Electrical Engineering Interview Questions
Real Electrical Engineering interview questions with answers. Filter by sub-field and difficulty, then drill them in practice mode.
Showing 80 of 80 questions
Beginner
Fundamentals, definitions, expected of any candidate
Intermediate
Applied reasoning, design tradeoffs, calculations
Advanced
Deeper scenario / system-design questions and edge cases (stretch material)
BeginnerFundamentals
State Ohm's Law and name where it does NOT hold.
fundamental knowledgeOhm's lawV=IR
BeginnerFundamentals
Explain Kirchhoff's Voltage Law (KVL) and Current Law (KCL).
fundamental knowledgeKVLKCLcircuit analysis
BeginnerFundamentals
What's the difference between AC and DC, and why is AC used for the grid?
fundamental knowledgeACDCtransmission
BeginnerFundamentals
How do a capacitor and an inductor store energy, and how do they behave in a circuit?
fundamental knowledgecapacitorinductorreactance
BeginnerFundamentals
What is impedance and how does it differ from resistance?
fundamental knowledgeimpedancereactancephasors
BeginnerFundamentals
Define power factor and explain why low power factor is a problem.
fundamental knowledgepower factorreal/reactive power
BeginnerFundamentals
Contrast single-phase and three-phase systems.
fundamental knowledgethree-phaseline/phase voltage
BeginnerFundamentals
What is a transformer and how does it work?
fundamental knowledgetransformerFaraday's lawturns ratio
BeginnerFundamentals
Difference between active and passive components? Conductor vs. insulator?
fundamental knowledgeactive/passiveconductorinsulator
BeginnerFundamentals
What is Thevenin's theorem and when is it useful?
fundamental knowledgeTheveninNortonequivalent circuit
BeginnerFundamentals
What's the difference between earthing (grounding) for safety vs. system grounding?
fundamental knowledgegroundingearthingsafety
BeginnerFundamentals
What's the difference between current and voltage?
fundamental knowledgecurrentvoltagecharge
BeginnerFundamentals
What does a diode do?
fundamental knowledgedioderectificationsemiconductor
BeginnerFundamentals
How does a transistor work, and how is it used as a switch?
fundamental knowledgetransistorBJTMOSFETswitch
BeginnerFundamentals
What's the difference between a BJT and a FET?
fundamental knowledgeBJTFETtransistor
BeginnerFundamentals
What are the properties of an ideal op-amp?
fundamental knowledgeop-ampvirtual shortfeedback
BeginnerFundamentals
What is a transistor?
fundamental knowledgetransistorsemiconductorswitchamplifier
BeginnerFundamentals
What are the three terminals of a BJT?
fundamental knowledgeBJTbasecollectoremitter
BeginnerFundamentals
What is RMS value and why do we use it for AC?
fundamental knowledgeRMSACeffective value
BeginnerFundamentals
What's the difference between real, reactive, and apparent power?
fundamental knowledgereal powerreactive powerapparent power
BeginnerFundamentals
Compare series and parallel circuits.
fundamental knowledgeseriesparallelcircuits
BeginnerFundamentals
How do you use nodal and mesh analysis?
fundamental knowledgenodal analysismesh analysisKVLKCL
BeginnerControls & Automation
Explain a PID control loop and what each term does.
PIDclosed-looptuningfeedback
IntermediateControls & Automation
What's the difference between a PLC and a DCS, and when would you use each?
PLCDCSSCADAarchitecture
BeginnerControls & Automation
Name the five IEC 61131-3 programming languages.
IEC 61131-3PLC programming
IntermediateControls & Automation
What's the difference between a Function Block (FB) and a Function (FC)?
PLCfunction blockscan cyclestate
IntermediateControls & Automation
A pressure transmitter outputs 4-20 mA. How does the PLC turn that into engineering units?
analog scaling4-20mAtransmitters
AdvancedControls & Automation
Describe how you'd implement a control system to transfer a gas (e.g., oxygen) from one tank to another.
system designprocess controlvalvesinterlocks
IntermediatePower Electronics
Draw a passive RC low-pass filter and characterize it.
low-pass filterRCcutoff frequencyroll-off
IntermediatePower Electronics
Draw a non-inverting op-amp amplifier and characterize it.
non-inverting amplifierop-ampgainvirtual short
AdvancedPower Electronics
Combine the RC low-pass filter and the non-inverting amp into an active low-pass filter. Write the gain at low and high frequency.
active low-pass filterop-ampgaincutoff frequency
IntermediatePower Electronics
Draw a buck converter and explain how it steps voltage down.
DC-DCbuck converterPWMduty cycle
IntermediatePower Electronics
How do you choose between a MOSFET and an IGBT?
MOSFETIGBTdevice selectionlosses
AdvancedPower Electronics
What parameters do you check on a MOSFET datasheet for a switching design?
MOSFETdatasheetRDS(on)gate charge
AdvancedPower Electronics
What are the main loss mechanisms in a switching converter?
conduction lossswitching lossefficiencyEMI
AdvancedPower Electronics
To get 12V out, is a 48V or 24V input better for the converter? Why?
buck converterduty cycletradeoff analysis
BeginnerRenewable Energy
What is MPPT and why does a solar system need it?
solar PVMPPTinverter
IntermediateRenewable Energy
How do you size PV strings, and what's the difference between a string and an array?
string sizingPV designtemperatureinverter window
IntermediateRenewable Energy
What factors affect wind turbine efficiency?
windturbine efficiencyBetz limit
AdvancedRenewable Energy
What is curtailment and why does it matter to project economics?
curtailmentgridproject economicsinterconnection
AdvancedRenewable Energy
What interconnection requirements apply to inverter-based resources?
interconnectionride-throughgrid-formingreactive power
BeginnerEmbedded Systems
What does the 'volatile' keyword do and when is it required?
volatileCISRhardware registers
BeginnerEmbedded Systems
How do you convert a hexadecimal number to binary?
hex to binarynumber systemsnibblebit manipulation
IntermediateEmbedded Systems
Write a function to set bits 3-5 of a 16-bit register to a value without touching other bits.
bit manipulationregistersmasking
AdvancedEmbedded Systems
How do you implement a single-producer/single-consumer ring buffer, and why must head/tail be volatile?
ring bufferFIFOvolatileconcurrencyUART
IntermediateEmbedded Systems
Explain interrupt handling best practices for ISRs.
interruptsISRRTOSlatency
AdvancedEmbedded Systems
How do you prevent priority inversion in an RTOS?
RTOSpriority inversionmutexscheduling
IntermediateEmbedded Systems
Describe the memory layout of a C program.
memory layoutstackheapbss
BeginnerPower Generation & Conversion
Explain how electricity is generated and then ends up in your home.
fundamental knowledgegenerationtransmissiondistributionstep-up/step-down
IntermediatePower Generation & Conversion
Give the torque and speed equations for a DC motor.
DC motortorqueback-EMFspeed control
AdvancedPower Generation & Conversion
How does excitation affect a synchronous generator's output?
synchronous generatorexcitationreactive powerAVR
IntermediatePower Generation & Conversion
Compare HVDC and HVAC transmission.
HVDCHVACtransmissionlosses
IntermediatePower Transmission & Distribution
What is the per-unit system and why is it used?
per-unitbase valuesload flow
AdvancedPower Transmission & Distribution
How do you calculate short-circuit / fault current?
fault analysissymmetrical componentsper-unitprotection
BeginnerPower Transmission & Distribution
Name the fault types and which are symmetrical vs. unsymmetrical.
fault typessymmetricalunsymmetrical
BeginnerPower Transmission & Distribution
What's the difference between a relay and a circuit breaker, and what does a protective relay do?
relaycircuit breakerprotection coordination
IntermediatePower Transmission & Distribution
What is load-flow (power-flow) analysis and why is it run?
load flowpower flowvoltageplanning
AdvancedSmart Grid & Energy Management
How do distributed energy resources (DER) change protection and planning?
DERhosting capacitybidirectional flowIBR
IntermediateSmart Grid & Energy Management
How do battery storage and hybridization improve renewable project value?
battery storagehybridizationgrid services
IntermediateSmart Grid & Energy Management
How does improved load forecasting help grid operations?
load forecastingdispatchplanning
BeginnerChip Design (VLSI/ASIC)
What is setup time and hold time?
setup timehold timeflip-flopSTA
IntermediateChip Design (VLSI/ASIC)
Compare ASIC and FPGA. When would you choose each?
ASICFPGAPPAtradeoff
IntermediateChip Design (VLSI/ASIC)
Walk me through the ASIC design flow from RTL to tape-out.
ASIC flowRTLsynthesisplace and routetape-out
AdvancedChip Design (VLSI/ASIC)
What is metastability and how do you deal with it?
metastabilitysynchronizerCDCMTBF
AdvancedChip Design (VLSI/ASIC)
What is clock domain crossing (CDC) and why is it a problem?
clock domain crossingCDCsynchronizerFIFO
IntermediateChip Design (VLSI/ASIC)
What's the difference between a latch and a flip-flop?
latchflip-floplevel-sensitiveedge-triggered
IntermediateChip Design (VLSI/ASIC)
What's the difference between blocking and non-blocking assignments in Verilog?
Verilogblockingnon-blockingrace condition
AdvancedChip Design (VLSI/ASIC)
A setup timing violation shows up after synthesis. How do you debug it?
setup violationcritical pathSTApipelining
BeginnerQuant Finance
What is expected value and why does it matter in trading?
fundamental knowledgeexpected valueEVprobability
IntermediateQuant Finance
What is arbitrage and what does 'no-arbitrage' mean?
fundamental knowledgearbitrageno-arbitragepricing
BeginnerQuant Finance
You flip a fair coin until it lands heads. What's the expected number of flips?
probability & brainteasersexpected valuegeometric distributionrecursioncoin
AdvancedQuant Finance
You have 100 coins: 99 fair, 1 double-headed. You pick one at random and flip 10 heads in a row. What's the probability it's the double-headed coin?
probability & brainteasersBayes theoremconditional probabilityupdating
IntermediateQuant Finance
What is the Central Limit Theorem and why does it matter?
statisticsCLTcentral limit theoremnormal distribution
BeginnerQuant Finance
What is the difference between a call and a put option?
derivatives & optionscallputoptionsstrike
IntermediateQuant Finance
Explain put-call parity.
derivatives & optionsput-call parityarbitrageoptions pricing
IntermediateQuant Finance
What are the option Greeks (delta, gamma, theta, vega)?
derivatives & optionsGreeksdeltagammathetavega
AdvancedQuant Finance
What is the intuition behind the Black-Scholes model?
derivatives & optionsBlack-Scholesdelta hedgingGBMimplied volatility
IntermediateQuant Finance
"Make me a market": I'll pay you the number of flips to get the first head. What do you quote?
markets & tradingmarket makingbid-askexpected valuespread
BeginnerQuant Finance
What is the bid-ask spread and what does it represent?
markets & tradingbid-ask spreadliquiditymarket maker
IntermediateQuant Finance
What is a Monte Carlo simulation and when would you use it in finance?
programming & modelingMonte Carlosimulationpricingrisk