Electrical system Exam 1 Latest Updated Questions and Verified Answers 2026
Edition.
Nikola Tesla Early proponent of alternating current; built AC generator
used to power the 1893 Chicago World's Fair
Michael Faraday Discovered that moving a magnet through a coiled copper wire
generates electric current
Georg Ohm Published a complete mathematical theory of electricity in 1827
George Westinghouse Developed AC power generating stations standardized at 60 Hz and
three-phase power; considered father of the modern electrical grid
Coulombs Unit of measure for static electric charge
Watts Unit of measure for electric power
Volts Unit of measure for electric potential
Ohms Unit of measure for electrical resistance
Switchgear Largest electrical distribution equipment; handles highest voltage and
current capacity
Low Voltage NEC category for 480-Volt 3-Phase power
Medium Voltage NEC category for 90,000-Volt 3-Phase power
, Ohm's Law Current equals voltage divided by resistance (I = V / R)
Kirchhoff's First Law The algebraic sum of currents entering and leaving a junction equals
zero
Hermetic Motor Completely sealed motor used in AC compressors; cooled by
refrigerant
TEAO (Totally Enclosed Air Over) Motor enclosed in steel shell with fins; requires air flowing over fins
for cooling
ODP (Open Drip Proof) Common general-purpose motor; protects against drips but allows
airflow for cooling
Capacitive Reactance Caused by insulation storage effect; current leads voltage
Impedance Combined effect of resistance and reactance
Inductive Reactance Common in motors; current lags voltage
Apparent Power Measured in kVA; voltage × current without considering reactance
Body Weight Does NOT affect severity of electrical shock
Transformer Changes AC voltage higher or lower
Inverter Converts DC to AC
Edition.
Nikola Tesla Early proponent of alternating current; built AC generator
used to power the 1893 Chicago World's Fair
Michael Faraday Discovered that moving a magnet through a coiled copper wire
generates electric current
Georg Ohm Published a complete mathematical theory of electricity in 1827
George Westinghouse Developed AC power generating stations standardized at 60 Hz and
three-phase power; considered father of the modern electrical grid
Coulombs Unit of measure for static electric charge
Watts Unit of measure for electric power
Volts Unit of measure for electric potential
Ohms Unit of measure for electrical resistance
Switchgear Largest electrical distribution equipment; handles highest voltage and
current capacity
Low Voltage NEC category for 480-Volt 3-Phase power
Medium Voltage NEC category for 90,000-Volt 3-Phase power
, Ohm's Law Current equals voltage divided by resistance (I = V / R)
Kirchhoff's First Law The algebraic sum of currents entering and leaving a junction equals
zero
Hermetic Motor Completely sealed motor used in AC compressors; cooled by
refrigerant
TEAO (Totally Enclosed Air Over) Motor enclosed in steel shell with fins; requires air flowing over fins
for cooling
ODP (Open Drip Proof) Common general-purpose motor; protects against drips but allows
airflow for cooling
Capacitive Reactance Caused by insulation storage effect; current leads voltage
Impedance Combined effect of resistance and reactance
Inductive Reactance Common in motors; current lags voltage
Apparent Power Measured in kVA; voltage × current without considering reactance
Body Weight Does NOT affect severity of electrical shock
Transformer Changes AC voltage higher or lower
Inverter Converts DC to AC
