# SSC JE Electrical Important MCQ Part 4

SSC JE Electrical Important MCQ PDF Part 4

1.The number of poles in a turbo alternator are

A) 10

B) 6

C) 2

D) 8

2.A/an ______ is used in electrical installation to join some conductors and provide different paths for different conductors.

A) Capacitor

B) Fuse

C) Ceiling rose

D) Junction box

Answer  : D (Junction boxes are metal or plastic enclosures used as housings for wiring connections. The connections within are called branch circuits and usually represent the end of a conduit run)

3.The number of depletion layers in a BJT transistor is-

A) Four

B) Three

C) Five

D) Two

4.The effect of fringing __________ with the increase in the length of the air gap in magnetic circuits.

A) Remains constant

B) Decreases

C) Becomes zero

D) Increases

Answer  : D (Fringing is directly proportional to the length of the air gap that means if the length increases the fringing effect will also be more and vice versa.)

5.Neutral is a circuit conductor that normally carries _________ back to the source.

A) Current

B) Power

C) Flux

D) Voltage

Answer  : A (Neutral is a circuit conductor that normally carries current back to the source, and is connected to ground (earth) at the main electrical panel)

6.The power factor of synchronous generator depends on

B) Core losses

C) Armature losses

D) Speed of rotor

7.Low resistance value can be measured accurately by using a/an

A) Megger

B) Ohmmeter

C) Kelvin double bridge

D) Multimeter

8.An SCR has _______ PN junctions.

A) 3

B) 4

C) 2

D) 5

9.An electric stove consumes 5 MJ of energy from a 230 V power supply when turned on for 60 minutes. Find the approximate power.

A) 1389 W

B) 1772 W

C) 1500 W

D) 1823 W

Answer  : A (P = W / t,P = (5 MJ) (106 J/MJ) / ((60 min) (60 s/min))=1389 W= 1.39 kW)

10.The frequency of an alternating quantity is

A) The speed with which the alternator runs

B) The number of direction reversals per second

C) The number of cycles completed per minute

D) The number of cycles completed per second

11.In which of the following applications is armoured cable used

A) Teak wood batten wiring

B) Domestic portable appliances

C) General wiring

D) Underground systems for distribution purpose

12.The average value of the current is the _____________ divided by the number of currents.

A) Sum of all resistances

B) Sum of all voltages

C) Sum of all currents

D) Sum of all currents and voltages

13.In a closed loop, the sum of voltage drops across components is equal to

A) Zero

B) Half the applied voltage

C) Twice the applied voltage

D) The applied voltage

14.________ at a point is defined as the force experienced per unit positive charge at a point placed in the electric field.

A) Magnetic flux density

B) Electric intensity

C) Electric flux

D) Voltage rating

15.The EMF of a generator depends on-

A) Number of poles

B) Number of parallel paths

C) Flux per pole

D) All of these

16.Which lamp has the best Colour Rendering Index (CRI)

A) Fluorescent

B) Incandescent

C) LED

D) High pressure sodium vapour

Answer  : B (The Color Rendering Index (CRI) is a scale from 0 to 100 percent indicating how accurate a “given” light source is at rendering color when compared to a “reference” light source.Fluorescent-76,Incandescent-100,LED-83,High pressure sodium vapour-24)

17.A multimeter can measure

A) All of the options

B) Voltage

C) Current

D) Resistance

18.What is the binary representation of 73

A) 1001100

B) 1001101

C) 1001001

D) 1001111

(Step 1: Divide (73)10 successively by 2 until the quotient is 0

73/2 = 36, remainder is 1
36/2 = 18, remainder is 0
18/2 = 9, remainder is 0
9/2 = 4, remainder is 1
4/2 = 2, remainder is 0
2/2 = 1, remainder is 0
1/2 = 0, remainder is 1

Step 2: Read from the bottom (MSB) to top (LSB) as 1001001.

So, 1001001 is the binary equivalent of decimal number 73)

19.The armature reaction affects the ___________ when the load on an alternator is increased.

A) Rotor speed

C) Frequency of armature

D) Terminal voltage

20.The expression for synchronous speed is _________ where Ns-synchronous speed, ffrequency,P-number of poles.

A) Ns = 120Pf

B) Ns = 120f/P

C) N s= 120P/f

D) Ns = 120/Pf