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 →
The function of a expansion tank (Conservator) in a power transformer is to:
AFilter out moisture from ambient air
BPrevent overvoltage transients
CTake up expansion and contraction of transformer oil during temperature changes
DCool the winding insulation directly
An enhancement-mode MOSFET conducts drain current only when gate-to-source voltage V_GS is:
ANegative for N-channel
BEqual to zero
CLess than breakdown voltage
DGreater than threshold voltage V_th
Which type of DC generator has the best voltage regulation under varying load conditions?
ADC Shunt generator
BFlat compounded DC generator
CDC Series generator
DOver compounded DC generator
The step angle of a 4-phase stepper motor having 200 rotor teeth is:
A1.8 degrees
B0.45 degrees
C7.5 degrees
D15 degrees
A Slip-Ring (Wound Rotor) Induction Motor is preferred over a Squirrel Cage motor when the application requires:
AMaximum speed exceeding synchronous speed
BMaintenance-free operation
CZero speed regulation
DHigh starting torque with low starting current
The form factor of a pure sinusoidal alternating current wave is defined as:
ARatio of Peak value to Average value
BRatio of Average value to Peak value (0.637)
CRatio of Peak value to RMS value (1.414)
DRatio of RMS value to Average value (1.11)
In an R-L series AC circuit, the overall circuit power factor is:
AZero leading
BUnity
CLeading
DLagging
In Delta to Star (Delta-Wye) conversion, the equivalent star resistance connected to a node is:
AProduct of two adjacent delta resistances divided by sum of three delta resistances
BProduct of three delta resistances divided by adjacent resistance
CDifference of adjacent delta resistances
DSum of three delta resistances divided by three
Which type of power amplifier operates with the collector current flowing for less than half (180 degrees) of the input AC cycle?
AClass A amplifier
BClass B amplifier
CClass C amplifier
DClass AB amplifier
The reciprocity theorem is applicable to electrical networks that are:
AUnilateral and non-linear
BNon-linear and active
CLinear, bilateral, and passive
DTime-variant and active