# ELECTRICAL 70 IMPORTANT MCQ PDF FOR VIZAG MT & MPVYAPAM SUB ENGINEER EXAM 2017

## ELECTRICAL 70 IMPORTANT MCQ Category –EE Online Test

Attempt Free ELECTRICAL 70 IMPORTANT MCQ Here. Read The Important Electrical MCQ From Below.

1.Charge on an electron is ?

a) 1.602 * 10-19 C.
b) 1.602 * 10-19 μC.
c) 9.107 * 10-31 C.
d) 9.107* 10-25 C.
ANS: (a)
2) An electron having mass ‘m’ kg and charge ‘e’ columb travels from rest through a potential difference of ‘V’ volts. It has a kinetic energy of ?
a) mV joules
b) m  eV joules
c) eV joules
d) m/e  joules
ANS: (c)
ELECTRICAL 70 IMPORTANT MCQ
3) A current is said to be direct current when its ?
a) magnitude remains constant with time
b) magnitude changes with time
c) direction changes with time
d) magnitude and direction changes with time
ANS: (a)
4) A current is said to be alternating when it changes in ?
a) magnitude only
b) direction only
c) both magnitude and direction
d) none
ANS: (c)
5) The generator develops an electric pressure by ?
a) conversion of heat
b) conversion of light
c) electro-magnetic induction
d) conversion of chemical energy
ANS: (c)
ELECTRICAL 70 IMPORTANT MCQ
6) The dc generator works on the principle of ?
a) Fleming’s left hand rule
b) Fleming’s right hand rule
c) Lenz’s law
d) none of the above
ANS: (b)
7) The basic function of a transformer is to change ?
a) level of the voltage
b) the power level
c) the power factor
d)  the frequency
ANS: (a)
8) Transformer is used ?
a) to step-up the voltage
b) to step-down the voltage
c) on d.c
d) to step-up or step-down the voltage
ANS: (d)
ELECTRICAL 70 IMPORTANT MCQ
9) An electron device means the device in which the conduction of electrons takes place through ?
a) a gas
b) vaccum
c) a semi-conductor
d) a gas, semi-conductor or vaccum
ANS: (d)
10) Which of the following is used as a passive component in an electronic circuit ?
a) vaccum diode
b) Zener diode
c) inductor
d) SCR
ANS: C
11) Which is a conventional source of energy ?
a) solar
c) geothermal
d) wind
ANS: (b)
12) The disadvantages of renewable source of energy is/are ?
a) intermittency
b) lack of dependability
c) availability in low energy densities
d) all the abaove
ANS: (d)
ELECTRICAL 70 IMPORTANT MCQ
13) Transmission lines connect ?
a) generating station to a switching station / step down transformer station.
b) step down transformer station to service transformer banks
c) distribution transformer to consumer premises
d) service points to consumer premises
ANS: (a)
14) A 3-phase 4-wire system is commonly used for ?
a) primary distribution
b) secondary distribution
c) primary transmission
d) secondary transmission
ANS: (b)
15 ) The basic elements of an electric drive are :
a) electric motor and the transmission system
b) electric motor ,the transmission and control system
c) the transmission and control system
d) electric motor and conversion equipment
ANS: (b)
16) The main draw back of electric drive is that:
a) it is cumbersome drive
b) it is costlier in intial as well as in maintenance cost
c) electric power supply failure makes the drive standstill
d) all of the above.
ANS: (c)
ELECTRICAL 70 IMPORTANT MCQ
17) The absolute measurement of resistance involves the measurement of ?
a) length and time
b) length and mass
c) velocity
d) either a or c
ANS : (d)
18 ) For absolute measurement of current the method commonly used is ?
a) electro-dynamometer method
b) tangent galvanometer method
c) Rayleigh current balance method
d) Lorenz method
ANS: (c)
19) Any physical system which does not automatically correct for variation in its output, is called ?
a) open loop system
b) closed loop system
c) unstable system
d) none of the above
ANS:(a)
ELECTRICAL 70 IMPORTANT MCQ
20) open loop control system is one in which the control action ?
a) depends on the input signal
b) is independent of the desired output
c) depends on system variables
d) depends on system size
ANS:(b)
21.The flow of electrical current in a conductor is due to flow of  ?
a) electrons.
b) protons.
c) electrons and ions.
d) charged particles.
ANS: (a)
22) An electric current is the ?
a) random movement of electrons in a conductor
b) movement of free electrons predominately in one direction
c) pressure difference between two poles
d) the power that causes drift of electrons.
ANS: (b)
23)The direction of current in an ac circuit ?
a) is from positive to negative.
b) is always in one direction.
c) varies from instant to instant.
d) cannot be determined.
ANS: (c)
ELECTRICAL 70 IMPORTANT MCQ
24) When an electric current is passed through a bucket full of water, lot of bubbling in there–the electric current is ?
a) ac.
b) dc.
c) pulsating.
d) none
ANS: (b)
25) Which device illustrates the principle of electro-mechanical conversion ? (asked in B.T.E M.P 1996)
a) Amplifier.
b)Battery charger.
c) Transformer.
d) Electric bell.
ANS: (a)
ELECTRICAL 70 IMPORTANT MCQ
26) Fleming’s left hand rule is applicable to ?
a) dc generator
b) dc motor
c) alternator
d) Transformer
ANS: (b)
27) In a transformer electrical power is transferred from one circuit to another with out change in ?
a) voltage
b) current
c) frequency
d)  turns
ANS: (C)
28) The frequency of a voltage at the secondary is ?
a) greater than that of primary
b) equal to that of primary
c) less than that of primary
d) none
ANS: (b)
ELECTRICAL 70 IMPORTANT MCQ
29) An example of solid state device is  ?
a) zener diode
b) triode
c) pentode
d) thyratron
ANS: (a)
30) Ratings on a capacitor are given 25μF , 12V. Also a plus sign is written near one of its terminals. The capacitor is  ?
a) mica capacitor
b) ceramic capacitor
c)electrolytic capacitor
d) paper capacitor
ANS: (C)
31) Which of the following power plants is the least reliable ?
a) wind
b) tidal
c) geothermal
d) solor
ANS: (a)
32) Which of the following power plants is the most reliable ?
a) diesel
b) Hydro-electric
c) steam
d) tidal
ANS: (b)
ELECTRICAL 70 IMPORTANT MCQ
POWER SYSTEMS
33) Which of the following is usually not the generating voltage ?
a) 6.6 KV
b) 11 KV
c) 12.5 KV
d) 13.2 KV
ANS: (c)
34) The highest transmission voltage in india is ?
a) 750 KV
b) 400 KV
c) 220 KV
d) 132 KV
ANS: (b)
35 ) DC motors are still preferred for use in ?
a) electric excavators  steel mills and cranes
b) lathes and machine tools
c) flour mills and jaw crushers
d) paper industry
ANS: (a)
ELECTRICAL 70 IMPORTANT MCQ
36) The  conversion of AC into DC can be affected by the use of ?
a) motor-generator set
b) mercury arc rectifier
c) silicon diodes
d) any of the above.
ANS: (d)
37) Zener diodes , when used as voltage standards ?
a) are forward biased
b) are reverse biased
c) cover a wide range of current
d) operate in breakdown strength
e) all of above except (a)
ANS : (e)
38 ) The material to be used in the manufacture of a standard resistor should be of ?
a) low resistivity
b) high resistivity and low temperature co-efficient
c) high temp co-efficient
d) low resistivity and high temperature co-efficient
ANS: (b)
39) Basic elements of a closed loop control system are the ?
a) feedback and controlled system
b) controller and controlled system
c) controlled system and servo system
d) feed back element and controlled system and controller
ANS:(d)
ELECTRICAL 70 IMPORTANT MCQ
40) A closed loop control system is basically different from open loop control system due to ?
a) feedback
b) servomechanism
c) actuating signal
d) error signal
ANS:(a)
41.Speed of the stator field of an Induction motor is
(a) Synchronous speed
(b) Any speed
(c) Less than Synchronous
(d) Slip Speed
Ans(a)
42.Difference in speed between stator field and rotor
(c)Slip
(d) Regulation
Ans:(c)Slip
ELECTRICAL 70 IMPORTANT MCQ
43.Frequency of current in rotor
(a)Supply frequency
(b)Less than supply frequency
(c)Greater than supply frequency
(d)Slip frequency
Ans;(d) Slip Frequency
44. Shape of the torque slip curve is
(a) Rectangular Hyperbola
(b)Parabola
(c)Sine
(d) Cosine
Ans;(a) Rectangular Hyperbola
45.Machine with negative slip
(a)Induction Motor
(b) Brake
(c)Induction Generator
(d)Synchronous machine
Ans(c) Induction Generator
46.When rotor is at standstill
(a)slip is zero
(b)slip is one
(c)Any slip
(d)Slip is infinity
Ans;(b)Slip is one
ELECTRICAL 70 IMPORTANT MCQ
47.When the motor runs at synchronous speed slip is
(a) One
(b) Infinity
(c)Zero
(d)Two
Ans:(c)Zero
48.Which torque is greater
(a)Break down
(d) Running
Ans:(a) Break down
49.An Induction motor is analogous to
(a)DC motor
(b)Transformer
(c)Synchronous motor
(d) DC Generator
Ans:(b)Transformer
50.Blocked rotor test is analogous to
(a) SC test
(b)OC test
(c)Swinburnes
Ans:(a)SC test
ELECTRICAL 70 IMPORTANT MCQ
51.No load test is analogous to
(a) SC test
(c)OC test
(d)Swinburnes test
Ans:(c)OC test
52.Rotor Copper loss is equal to
(a)Friction loss
(b)Stator loss
(c)slip times rotor input
(d)rotational loss
Ans: (c)slip times rotor input
53.For the purpose of plugging
(a)N is positive w.r.t to Ns
(b)N is zero
(c)N is infinity
(d)N is negative w.r.t to Ns
Ans: (d)N is negative w.r.t to Ns
54.Parameter from no load test is
(a)Ri and Xi
(b)Ro and Xo
(c) Copper loss
(d)Impedance
Ans:(b)Ro and Xo
ELECTRICAL 70 IMPORTANT MCQ
55.If stator field is rotating in clockwise direction rotor rotates in
(a) Any direction
(b)Cannot predict
(c)Anticlockwise
(d) clockwise
Ans: (d)clockwise
66.Blocked rotor test is conducted at
(a)High voltage
(b)Rated current
(c)High current
(d)Rated voltage
Ans(b)Rated current
67.Speed of rotor field in space
(a)N
(b)Any speed
(c)Ns
(d)Slip speed
Ans(c)Ns
ELECTRICAL 70 IMPORTANT MCQ
68.Line joining tangent and output line in a circle diagram gives
(a)Cu loss
(b)Stator loss
(c)Maximum output
(d)Maximum Torque
Ans;(c)maximum Output
69..Line joining tangent and Torque line in a circle diagram gives
(a)Cu loss
(b)Stator loss
(c)Maximum output
(d)Maximum Torque
Ans;(d)maximum Torque

70.No load test is conducted at
(a)High voltage
(b)Rated current
(c)High current
(d)Rated voltage

Ans: (d)Rated voltage

ELECTRICAL 70 IMPORTANT MCQ