Electrical Engineering Question Answers

Question No. 1. A potentiometer may be used for
(a) measurement of resistance
(b) measurement of current
(c) calibration of ammeter
(d) calibration of voltmeter
(e) all of the above
Answer: (e) all of the above

Question No. 2. A dc shunt generator has a speed of 800 rpm when delivering 20 A to the load at the
terminal voltage of 220V. If the same machine is run as a motor it takes a line
current of 20A from 220V supply. The speed of the machine as a motor will be
(A) 800 rpm.
(B) more than 1000 rpm.
(C) less than 800 rpm.
(D) both higher or lower than 800 rpm.
Answer: (C) less than 800 rpm.

Question No. 3. In order to reduce the harmonics in the emf generated in an alternator

(A) slots are skewed
(B) salient pole tips are chamfered
(C) winding is well distributed
(D) all of the above.

Answer: (D) all of the above.

Question No. 4. The use of _____ instruments is merely confined within laboratories as stand¬ardizing
instruments.
(a) absolute
(b) indicating
(c) recording
(d) integrating
(e) none of the above
Answer: (a) absolute



Question No. 5. Two transformers operating in parallel will share the load depending upon their
 (A) Rating.
(B) Leakage reactance.
(C) Efficiency.
(D) Per-unit impedance.
Answer:  (A) Rating.

Question No. 6.. In large generators protection provided against external faults is

(A) biased differential protection
(B) sensitive earth fault protection
(C) inter-turn fault protection
(D) all of the above.

Answer: (D) all of the above.

Question No. 7. Volt box is a component to
(a) extend voltage range
(6) measure voltage
(c) compare voltage in a box
(d) none of the above
Answer: a

Question No. 8. A single phase Hysteresis motor
 (A) can run at synchronous speed only
 (B) can run at sub synchronous speed only
 (C) can run at synchronous and super synchronous speed
 (D) can run at synchronous and sub synchronous speed

 Answer:  (A) can run at synchronous speed only


Question No. 9. Which type of protection is provided on a generator to protect against stator insulation failure ?

(A) Differential protection
(B) Thermocouple actuated alarm
(C) Over current relay
(D) Reverse power relay.

Answer: (A) Differential protection

Question No. 10. It is required to measure the true open circuit e.m.f. of a battery. The best device is
(a) D.C. voltmeter
(b) Ammeter and a known resistance
(c) D.C. potentiometer
(d) None of the above
Answer: (c) D.C. potentiometer

Electrical Engineering Question Answers- Feb 2018

Question No. 1. The d.c. series motor should always be started with load because
(A) at no load, it will rotate at dangerously high speed.
(B) it will fail to start.
(C) it will not develop high starting torque.
(D) all are true.
 Ans: A

Question No. 2. The armature of a dc machine is laminated to reduce:
(A) Eddy current loss
(B) Hysteresis loss
(C) copper losses
(D) friction and windage losses
 Ans: A

Question No. 3. The frequency of the rotor current in a 3 phase 50 Hz, 4 pole induction motor at full
load speed is about
(A) 50 Hz.
(B) 20 Hz.
(C) 2 Hz.
(D) Zero.
 Ans: C

Question No. 4. If a single phase alternator has 8 slots per pole uniformly speed, but the winding is arranged with the middle two left empty, the breadth coefficient will be

(A) 0.53.
(B) 0.88

(C) 0.67
(D) 0.99
Answer: (A) 0.53.

Question No. 5. In DC generators, armature reaction is produced actually by
 (A) Its field current. (B) Armature conductors.
 (C) Field pole winding. (D) Load current in armature.
Ans: D

Question No. 6. A synchronous motor is operating on no-load at unity power factor. If the field
 current is increased, power factor will become
(A) Leading & current will decrease
(B) Lagging & current will increase.
(C) Lagging & current will decrease.
(D) Leading & current will increase.
Ans: A

Question No. 7. An a.c. tachometer is just a ________with one phase excited from the carrier
frequency.
(A) two-phase A.C. servomotor (B) two-phase induction motor
(C) A.C. operated universal motor (D) hybrid stepper motor.
Ans: D

Question No. 8. Oil-filled cable has a working stress of __________ kV/mm
(A) 10 (B) 12
 (C) 13 (D) 15
 Ans: D
 This is defined by dielectric strength of mineral oil i.e. 15 kV/mm.


Question No.9. Which relays comes into operation in the event of the failure of prime mover connected to ihe generator ?
(A) Buchholz relay
(B) Differential relay
(C) Reverse power relay
(D) None of the above.

Answer; (C) Reverse power relay


A ceiling fan uses
 (A) split-phase motor.
(B) capacitor start and capacitor run motor.
(C) universal motor.
(D) capacitor start motor.
Ans: D
 To give starting torque and to maintain speed.

Electrical Engineering Question Answers- Jan 2018

Q.#1. The resistance of armature winding depends on
(a) length of conductor
(b) cross-sectional area of the conductor
(c) number of conductors
(d) all of the above
Ans: (d) all of the above

Q.#2. A commutator in a d.c. machine
 (A) Converts the induced a.c armature voltage into direct voltage.
 (B) Reduces power loss in field circuit.
 (C) Reduces power loss in armature.
 (D) Is not necessary.
Ans:  (A) Converts the induced a.c armature voltage into direct voltage.

Q.#3. In D.C. generators, the cause of rapid brush wear may be
(a) severe sparking
(b) any of the above
(c) imperfect contact
(d) rough commutator surface
Ans: (b) any of the above


Q.#4. The introduction of interpoles in between the main pole improves the performance of
d.c. machines, because
(A) A counter e.m.f. is induced in the coil undergoing commutation.
(B) The flux waveform is improved with reduction in harmonics.
(C) The inequality of air flux on the top and bottom halves of armature is removed.
(D) The interpole produces additional flux to augment the developed torque.
Ans: (A) A counter e.m.f. is induced in the coil undergoing commutation.

Q.#5. A differentiator is usually not a part of a control system because it
(a) increases input noise
(b) reduces the gain margin
(c) reduces damping
(d) increases error
Ans: (a) increases input noise

Q.#6. In D.C. generators, the brushes on commutator remain in contact with conductors
which
(a) lie under interpolar region
(b) lie under north pole
(c) lie under south pole
(d) are farthest from the poles
Ans: (a) lie under interpolar region

Q.#7. In induction motor, percentage slip depends on
(a) supply frequency
(b) copper losses in motor
(c) supply voltage
(d) none of the above
Ans:  (b) copper losses in motor

Q.#8. A 1:5 step-up transformer has 120V across the primary and 600 ohms resistance
across the secondary. Assuming 100% efficiency, the primary current equals
(A) 0.2 Amp.
(B) 5 Amps.
(C) 10 Amps.
(D) 20 Amps.
Ans: (A) 0.2 Amp.


Q.#9. Less maintenance troubles are experienced in case of
(a) slip ring induction motor
(b) squirrel cage induction motor
(c) both (a) and (b)
(d) none of the above
Ans: (b) squirrel cage induction motor

Q.#10. The spring material used in a spring control device should have the following property.
(a) Should be non-magnetic
(b) Most be of low temperature co-efficient
(c) Should have low specific resistance
(d) Should not be subjected to fatigue
(e) All of the above
Ans: (e) All of the above

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Mechanical Engineering Multiple Choice Questions

Q1. The buckling load for a column pinned at both ends is 10 kN. If the ends are fixed, the buckling load changes to
(1) 40 kN
(2) 2·5 kN
(3) 5 kN
(4) 20 kN
Q2. A 30 mm hole/shaft assembly results in minimum and maximum clearance of 0·03 mm and 0·3 mm respectively. The hole has a unilateral tolerance with zero fundamental deviation. If the tolerance of
the shaft is 0·08 mm, the maximum size of the hole is
(1) 30·11 mm
(2) 30·16 mm
(3) 30·19 mm
(4) 30·27 mm

Q3. Consider the following drives :
A. V-belt
B. Flat belt
C. Toothed belt
D. Round belt
Which of the above is/are positive drive(s) ?
Select the code for the correct answer from the options given below :
(1) A and B only
(2) B only
(3) C only
(4) C and D only


Q4. Bolts in the flanged end of a pressure vessel are usually pre-tensioned. Indicate which of the following
statements is not true :
(1) Pre-tensioning helps to seal the pressure vessel.
(2) Pre-tensioning reduces the maximum tensile stress in the bolts.
(3) Pre-tensioning increases the fatigue life of the bolts.
(4) Pre-tensioning helps to reduce the effect of pressure pulsations in the pressure vessel.

Q5. Which of the following are the third inversions of slider crank mechanism ?
A. Oscillating cylinder engine
B. Hand pump
C. Rotary engine
D. Crank and slotted lever
Select the code for the correct answer from the options given below :
(1) A and B only
(2) A and D only
(3) A, B and D only
(4) All of the above

Q6. Which of the following governors is/are not suitable for high speeds ?
A. Watt Governor
B. Hartnell Governor
C. Hartung Governor
D. Wilson-Heartnell Governor

Select the code for the correct answer
from the options given below :
(1) C only
(2) A only
(3) Both A and C
(4) Both C and D

Q7. Net Strain Gauge is
(1) An active device and converts mechanical displacement into change of resistance.
(2) A passive device and converts mechanical displacement into change of resistance.
(3) A passive device and converts electrical displacement into change of resistance.
(4) An active device and converts electrical displacement into change of resistance.

Q8. Which theory(ies) of failure will you use for aluminium under static loading ?
A. Principal Stress Theory
B. Principal Strain Theory
C. Strain Energy Theory
D. Maximum Shear Stress Theory
Select the code for the correct answer from the options given below :
(1) A and D only
(2) C and D only
(3) B only
(4) D only

Q9. Which of the following statements is true ?
(1) Below 910C, pure iron exists in FCC crystal structure.
(2) Between 1537C and 1400C, iron exists as pearlite.
(3) In the iron-carbon equilibrium diagram the eutectic point is at 6·67% of C.
(4) None of these

Q10. The effect of cobalt in a steel alloy is
(1) to increase red hardness and sustain hardness during tempering.
(2) to increase softness and weldability.
(3) to promote deoxidisation and nitriding.
(4) to promote grain growth and machinability.


Q11. The main objects of annealing are
(1) To refine grain size and to relieve internal stresses.
(2) To alter electrical and magnetic properties.
(3) To remove gases trapped in the metal during initial casting.
(4) All of the above

Q12. By the law of belting
(1) Two non-parallel shafts can be run in either direction without any intermediation.
(2) A guide pulley helps two non-parallel shafts to run in either direction.
(3) The centre line of the belt when it approaches an idler pulley should be at the edge of the plane.
(4) All of the above

Q13. In an S.I. engine, when most economical mixture is supplied, the colour of exhaust gases can be expected to be
(1) Bluish
(2) Dark red
(3) Dark blue and reddish yellow
(4) White

Q14. For carbon-carbon composites, the following statement(s) is/are true :
(1) C-C composites are structures in which both matrix and the reinforcement are carbon.
(2) C-C composites have high temperature strength and toughness.
(3) The high cost of C-C composites is a major issue.
(4) All of the above

Q15. Consider the following statements in relation to composite materials.
A. A composite material is a structural material created synthetically or  artificially by combining two ormore materials having dissimilar characteristics.
B. The constituents are combined at macroscopic level and are not soluble in each other.
C. One constituent is called as matrix phase and the other is called as reinforcing phase.
D. Reinforcing phase is embedded in the matrix phase.
Which of the above statements is/are correct ? Select the code for the correct answer from the options given below :
(1) A only
(2) A, B and C only
(3) A and C only
(4) None of the above

Q16. A dehumidifier is required in
(1) A winter air-conditioning system
(2) A summer air-conditioning system
(3) Filters for removing dust particles
(4) A duct where air is circulated into required space

Q17. Which of the following would not increase the rate of heat transferred from a heater pipe ?
(1) Insulating with materials whose thickness is below that of critical thickness for insulation.
(2) Providing cooling jackets over the heater pipe surface.
(3) Providing heat exchangers.
(4) Covering heater pipe with another pipe whose thermal conductivity is smaller in number and 50 mm
thick.

Q18. A screw thread is obtained (1) When the hypotenuse of a right-angled triangle is wrapped
around the circumference of a cylinder.
(2) When a point moves on the circumference of a cylinder at a ratio of diameter to the pitch of thread.

(3) When a line moves on the circumference of a cylinder with an angle parallel to its axis.
(4) When one of the sides of an equilateral triangle is wrapped around the circumference of a
cylinder.

Q19.In the open channels, the specific energy is the
(1) total energy per unit discharge
(2) total energy measured with respect to the datum passing through the bottom of the channel
(3) total energy measured above the horizontal datum
(4) total energy per velocity of flow

Q20. For a perfect incompressible liquid flowing in a continuous stream, the total energy of a particle remains the same while the particle moves from one point to another. This statement is called
(1) Continuity equation
(2) Bernoulli’s equation
(3) Pascal’s law
(4) Archimedes’ principle

Click here to download complete question paper in pdf. format(Total 100 Questions)

Electrical Engineering Questions With Answer

1. D.C. generator generally preferred for charging automobile batteries is
(a) series generator
(b) shunt generator
(c) long shunt compound generator
(d) any of'the above
Ans: c
2. No-load current in a transformer
(a) lags behind the voltage by about 75°
(b) leads the voltage by about 75°
(c) lags behind the voltage by about 15°
(d) leads the voltage by about 15°
Ans: a

3. Primary winding of a transformer
(a) is always a low voltage winding
(b) is always a high voltage winding
(c) could either be a low voltage or high voltage winding
(d) none of the above
Ans: c

4. Power transformers are designed to have maximum efficiency at
(a) nearly full load
(b) 70% full load
(c) 50% full load
(d) no load
Ans: a


5. In a transformer the tappings are generally provided on
(a) primary side
(b) secondary side
(c) low voltage side
(d) high voltage side
Ans: c

6. Transmission voltage of llkV is normally used for distances upto
(a) 20—25 km
(b) 40—50 km
(c) 60—70 km
(d) 80—100 km
Ans: a

7. When a live conductor of public electric supply breaks down and touches the earth
which of the following will happen ?
(a) Current will flow to earth
(b) Supply voltage will drop
(c) Supply voltage will increase
(d) No current will flow in the conductor
(e) None of the above
Ans: a

8. D.C. series generator is used
(a) to supply traction load
(b) to supply industrial load at constant voltage
(c) voltage at the toad end of the feeder
(d) for none of the above purpose
Ans: c


9. The thickness of the layer of insulation on the conductor, in cables, depends upon
(a) reactive power
(b) power factor
(c) voltage
(d) current carrying capacity
Ans: c

10. In D.C. generators on no-load, the air gap flux distribution in space is
(a) sinusoidal
(b) triangular
(c) pulsating
(d) flat topped
Ans: d

Electrical Engineering Questions with Answer

Question No. 1. Electric resistance seam welding uses __________ electrodes.
 (A) Pointed
(B) Disc.
 (C) Flat
(D) Domed
Ans: B

Question No. 2. Spring constant in force-voltage analogy is analogous to
(a) capacitance
(b) reciprocal of capacitance
(c) current
(d) resistance
Ans: b

Question No. 3. The frequency and time domain are related through which of the following?
(a) Laplace Transform and Fourier Integral
(b) Laplace Transform
(c) Fourier Integral
(d) Either (b) or (c)
Ans: a

Question No. 4. When the initial conditions of a system are specified to be zero it implies that the
system is
(a) at rest without any energy stored in it
(b) working normally with reference input
(c) working normally with zero reference input
(d) at rest but stores energy
Ans: d


Question No. 5. The power of a n-phase circuit can be measured by using a minimum of
(a) (n - 1) wattmeter elements
(b) n wattmeter elements
(c) (n + 1) wattmeter elements
(d) 2n wattmeter elements
Ans: a

Question No. 6. As compared to shunt and compound DC motors, the series DC motor will have the
highest torque because of its comparatively ____________ at the start.
 (A) Lower armature resistance. (B) Stronger series field.
 (C) Fewer series turns. (D) Larger armature current.
Ans: D

Question No. 7. The transfer function is applicable to which of the following ?
(a) Linear and time-in variant systems
(b) Linear and time-variant systems
(c) Linear systems
(d) Non-linear systems
(e) None of the above
Ans: a

Question No. 8. The rotor power output of a 3-phase induction motor is 15 KW and corresponding slip
is 4%. The rotor copper loss will be
 (A) 600 W. (B) 625 W
 (C) 650 W (D) 700 W
Ans: B


Question No. 9. Zero initial condition for a system means
(a) input reference signal is zero
(b) zero stored energy
(c) ne initial movement of moving parts
(d) system is at rest and no energy is stored in any of its components
Ans: d

Question No. 10. The maximum power for a given excitation in a synchronous motor is developed
when the power angle is equal to
 (A) 0o
 (B) 45o
 (C) 60o
 (D) 90o
Ans: A

Civil Engineering Exam Questions- 2017

Question # 1. Euler’s formula holds good only for
(1) Short columns
(2) Long columns
(3) Both short and long columns
(4) Intermediate columns

Question # 2. The vehicle used in case of enamel paints is usually
(1) Linseed oil
(2) Water
(3) Varnish
(4) None of the above

Question # 3. Closed contours of decreasing values
towards their centre, represent a
(1) Hill
(2) Depression
(3) Saddle
(4) River bed

Question # 4. Maximum bulking of sand is likely to occur at a moisture content of
(1) 5%
(2) 8%
(3) 11%
(4) 14%


Question # 5. The operation of revolving a plane table about its vertical axis so that all lines on
the sheet become parallel to corresponding lines on the ground is known as
(1) Levelling
(2) Centering
(3) Orientation
(4) Setting

Question # 6. Which of the following aggregates gives maximum strength in concrete ?
(1) Rounded aggregate
(2) Elongated aggregate
(3) Flaky aggregate
(4) Cubical aggregate

Question # 7. Plasticizers and superplasticizers are used to
(1) Reduce C/W ratio
(2) Increase workability
(3) Increase strength
(4) All of the above

Question # 8. As per IRC (Indian Road Congress), the maximum possible width of a vehicle will be
(1) 2·44 m
(2) 3·44 m
(3) 1·88 m
(4) 4·0 m

Question # 9. The value of the property shown in the account books after allowing necessary depreciation is called as
(1) Scrap value
(2) Salvage value
(3) Book value
(4) Market value


Question # 10. Which of the following is common, when a valve closes suddenly at an end of a pipeline system, and a pressure wave propagates in the pipe ?
(1) Expansion
(2) Contraction
(3) Water hammer
(4) Turbulent flow

Question # 11. Coning of wheels is provided (1) To check lateral movement of
wheels
(2) To avoid damage to inner faces of rails
(3) To avoid discomfort to passengers
(4) All of the above

Question # 12. The initial setting time for ordinary portland cement as per IS specification
should not be less than
(1) 10 minutes
(2) 30 minutes
(3) 60 minutes
(4) 600 minutes

Question # 13. The IS code used for the design of RC elements is
(1) IS 875
(2) IS 800
(3) IS 456
(4) IS 8112


Question # 14. The slope of voids ratio versus log of effective stress for a soil specimen gives
(1) Coefficient of compressibility
(2) Coefficient of volume change
(3) Coefficient of consolidation
(4) Compression index

Question # 15. Water supply to a house begins with connection of the service pipe with municipal water mains. The connection sequence comprises
A. Stopcock
B. Gooseneck
C. Ferrule
D. Water meter