Electrical Engineering
Electrical Engineering MCQs with Answers
Electrical engineering MCQs with answers and detailed explanations for PEC, NTS, WAPDA and engineering job tests. Machines, circuits and power systems. Take a scored quiz instead →
Which distance relay is least affected by arc resistance and is preferred for short transmission lines?
AReactance relay
BImpedance relay
CMho relay
DThermal relay
Buchholz relay is a gas-actuated protective relay used exclusively for:
ASynchronous motors
BHigh-voltage alternators
CAir-cooled transformers
DOil-immersed transformers
The Merz-Price circulating current scheme for transformer protection operates on the principle of:
AOvercurrent protection
BNegative sequence detection
CDifferential protection
DDistance relaying
Which power system fault is classified as a symmetrical fault?
ASingle line-to-ground fault
BDouble line-to-ground fault
CThree-phase fault (L-L-L or L-L-L-G)
DLine-to-line fault
Bundled conductors are widely used in High Voltage (HV) and Extra High Voltage (EHV) transmission lines to:
AIncrease mechanical tension
BEliminate skin effect entirely
CReduce conductor weight
DReduce corona loss and line reactance
Proximity effect in a transmission line conductor results in:
ADecrease in effective line resistance
BComplete cancellation of line inductance
CNon-uniform current distribution due to magnetic flux from neighboring conductors
DUniform current distribution across cross-section
Which type of fault in a 3-phase power transmission line is the most frequent?
ADouble Line-to-Ground (L-L-G) fault
BSingle Line-to-Ground (L-G) fault
CLine-to-Line (L-L) fault
DSymmetrical Three-Phase fault (L-L-L)
The surge impedance of an underground cable is significantly lower than overhead lines, usually around:
A40 to 50 ohms
B5 to 10 ohms
C1000 ohms
D400 to 500 ohms
An over-excited synchronous motor operating on no-load acts as a:
ASynchronous condenser
BInductive load
CResistive heater
DStep-down transformer
The surge impedance of a typical overhead transmission line is approximately in the range of:
A400 to 500 ohms
B10 to 20 ohms
C1000 to 2000 ohms
D40 to 50 ohms