Departmental (other) • 2025 • Paper-II
An electrical system is considered solidly earth
A)
if it is directly connected to earth electrode
B)
if it connected to earth electrode through fuse wire
C)
if it connected to earth electrode through earth switch
D)
if it connected to earth electrode through circuit breaker
Option A is correct: if it is directly connected to earth electrode.
Departmental (other) • 2025 • Paper-II
The most commonly used cell is
A)
lead-acid cell
B)
nickle-iron cell
C)
nickle-cadmium cell
D)
fuel cell
Option A is correct: lead-acid cell.
Departmental (other) • 2025 • Paper-II
When power factor is increased
A)
active power increases
B)
active power decreases
C)
line current increases
D)
line current decreases
Option D is correct: line current decreases.
Departmental (other) • 2025 • Paper-II
What are the factors upon which the choice of span in overhead transmission line depends?
Departmental (other) • 2025 • Paper-II
Kirchoff’s law is not applicable to circuits with
A)
non-linear resistance
B)
passive elements
C)
distributed parameters
D)
lumped parameters
Option C is correct: distributed parameters.
Departmental (other) • 2025 • Paper-II
Out of the following, the most accurate measurement of unknown resistance will be by
A)
potentiometer
B)
ohmmeter
C)
voltmeter and ammeter
D)
Wheatstone bridge
Option D is correct: Wheatstone bridge.
Departmental (other) • 2025 • Paper-II
Which of the following instrument will always indicate true rms values irrespective of the waveform ?
A)
Thermocouple meter
B)
Digital voltmeter
C)
Moving iron meter
D)
Electrostatic voltmeter
Option C is correct: Moving iron meter.
Departmental (other) • 2025 • Paper-II
When lead-acid cell is fully charged
A)
anode is converted into Pb
B)
Cathode is converted into PbO2
C)
Specific gravity of H2SO4 rises to about 1.28
D)
both plates becomes red
Option C is correct: Specific gravity of H2SO4 rises to about 1.28.
Departmental (other) • 2025 • Paper-II
Briefly describe star-delta starting and mention its de-merits.
Departmental (other) • 2025 • Paper-II
Power factor is the ratio of
A)
average power/apparent power
B)
apparent power/reactive power
C)
reactive power/ average power
D)
apparent power/ average power
Option A is correct: average power/apparent power.
Departmental (other) • 2025 • Paper-II
Which of the following instrument is free from hysteresis and eddy current errors?
A)
Moving iron instrument
B)
PMMC instrument
C)
Electrostatic instrument
D)
Dynamometer instrument
Option C is correct: Electrostatic instrument.
Departmental (other) • 2025 • Paper-II
The external PT ratio is 33000/110V and external CT ratio is 400/1A. If the energy meter is calibrated for PT ratio 33000/110V, CT ratio -/1A then what will be the multiplying factor for the meter?
Departmental (other) • 2025 • Paper-II
Kirchoff’s law is applicable to .
A)
AC circuits only
B)
DC circuits only
C)
both AC and DC circuits
D)
passive networks only
Option C is correct: both AC and DC circuits.
Departmental (other) • 2025 • Paper-II
What are the advantages of oil over air as a cooling medium in transformer?
Departmental (other) • 2025 • Paper-II
The e.m.f of a cell does not depend upon
A)
nature of electrolyte
B)
nature of material of electrolyte
C)
concentration of electrolyte
D)
size and spacing of electrodes
Option D is correct: size and spacing of electrodes.
Departmental (other) • 2025 • Paper-II
An ammeter is
A)
secondary instrument
B)
absolute instrument
C)
recording instrument
D)
integrating instrument
Option A is correct: secondary instrument.
Departmental (other) • 2025 • Paper-II
Which resistance material is preferred for standards?
A)
Manganin
B)
Platinum
C)
Nichrome
D)
German silver
Option A is correct: Manganin.
Departmental (other) • 2025 • Paper-II
Improving power factor means making it
A)
close to unity
B)
zero
C)
less than 0.5
D)
more than 0.5
Option A is correct: close to unity.
Departmental (other) • 2025 • Paper-II
A power factor meter have
A)
only current coil
B)
only voltage coil
C)
both current and voltage coil
D)
only inductive voltage coil
Option C is correct: both current and voltage coil.
Departmental (other) • 2025 • Paper-II
Earthing of transformer neutral is usually done through reactance to
A)
improve transient stability
B)
improve steady state stability
C)
improve transient as well as steady state stability
D)
reduce steady state stability
Option A is correct: improve transient stability.
Departmental (other) • 2025 • Paper-II
Which of the following factor affects resistivity of metals?
A)
Age hardening
B)
Alloying
C)
Temperatures
D)
Cold works
Option C is correct: Temperatures.
Departmental (other) • 2025 • Paper-II
Petroleum jelly is applied on the electrical connections to the lead acid battery to
A)
prevent short circuiting
B)
prevent corrosion
C)
prevent local heating
D)
reduce path resistance
Option B is correct: prevent corrosion.
Departmental (other) • 2025 • Paper-II
Superconductivity of materials can be destroyed by
A)
Application of magnetic field
B)
Increasing temperature
C)
Reducing temperature
D)
Adding impurities
Option B is correct: Increasing temperature.
Departmental (other) • 2025 • Paper-II
Copper becomes super conductive
A)
when 100% pure
B)
when electro refined
C)
at very high temperatures
D)
at absolute zero
Option D is correct: at absolute zero.
Departmental (other) • 2025 • Paper-II
Galvanizing is the process of coating materials with a layer of
A)
aluminium
B)
copper
C)
zinc
D)
nickel
Option C is correct: zinc.
