Departmental (other) • 2025 • Paper-II
What are the advantages of wound rotor motors over squirrel cage motors?
Departmental (other) • 2025 • Paper-II
Briefly describe star-delta starting and mention its de-merits.
Departmental (other) • 2025 • Paper-II
A sulphated battery usually gives
A)
low ampere hour capacity
B)
low voltage
C)
low specific gravity
D)
all of the above
Option D is correct: all of the above.
Departmental (other) • 2025 • Paper-II
Surge absorbers are used for protection against
A)
High-voltage low-frequency oscillations
B)
High-voltage high-frequency oscillations
C)
Low-voltage high-frequency oscillations
D)
Low-voltage low-frequency oscillations
Option B is correct: High-voltage high-frequency oscillations.
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
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
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
What are the factors upon which the choice of span in overhead transmission line depends?
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.
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
“In a linear network containing bilateral impedances and generators, the ratio of voltage V introduce in one mesh to the current I in any second mesh is the same as the ratio obtained if the position of V and I are interchanged, other emf being removed.” The above statement is associated with
A)
Superposition theorem
B)
Thevenin’s theorem
C)
Norton’s theorem
D)
Millman’s theorem
Option A is correct: Superposition theorem.
Departmental (other) • 2025 • Paper-II
What are the advantages of oil over air as a cooling medium in transformer?
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
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
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
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
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
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
Mention the conditions to be met for paralleling Alternator with infinite busbar.
Departmental (other) • 2025 • Paper-II
What are the factors upon which the potential barrier of a pn junction depends?
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
What causes sulphation in lead-acid battery? How will you get rid of it?
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
“Any network with two open terminals a and b can be replaced by a single voltage source V in series with a single resistance R driving the ab terminals.” The above statement is associated with
A)
Superposition theorem
B)
Thevenin’s theorem
C)
Norton’s theorem
D)
Millman’s theorem
Option B is correct: Thevenin’s theorem.
