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Special Free Session – 3 PM

SUBJECT – Control system

SSC JE – 5 PM (Under SSC Subscription)

SUBJECT – BEE (Basic Electrical Engineering)

UPPSC AE – 7 PM (Under UPPSC subscription)

SUBJECT – Control System

SSC JE – 9 PM

Crash course of SSC JE with MCQs

ashishsoniwifistudy

1. The energy stored in the magnetic field of a

solenoid 10 cm long and 2 cm diameter, with 1000

turns of carrying current of 10A is [UPSSC 2015]

a) 1.15J

b) 0.015J

c) 0.19J

d) 0.5J

2. A bar of Iron 1 cm² in cross section has 10−4 Wb of

Magnetic Flux in it, If μr = 2000 . What is the

Magnetic field intensity in the bar? [S.S.C.J.E. 2015]

a) 398 × 104AT

m

b) 𝟑𝟗𝟖𝐀𝐓

𝐦

c) 398 × 10−4AT

m

d) 796 × 10³AT

m

3. The magnitude of AT required to establish a given

value of Flux in the air gap will be much greater

than that required for Iron part of a magnetic circuit,

because: [S.S.C.J.E. 2015]

a) air has the lowest relative permeability

b) iron has the lowest permeability

c) air is a gas

d) air is a good conductors of magnetic flux

4. A conductor is rotated in a magnetic field. the

direction of the induced emf can be found by

application of A conductor is rotated in a magnetic

field. The direction of the induced emf can be found

by application of– [UPRVUNL 2014]

a) Faraday Law

b) Lena’s Law

c) Fleming’s right hand rule

d) Flemings left hand rule

5. A straight conductor of 100 cm in length, moves

with a uniform velocity of 2 m/s at right angles to

itself and to a uniform magnetic field of Flux density

1 Wb/m². the value of induced e.m.f between the

ends of the conductor is [SBNL TTA JE 2015]

a) 200 V

b) 0 V

c) 1 V

d) 2 V

6. The magnetic Flux density in an air-cooled coils is10−2 wb/m². With cast iron relative permeability 100

inserted, the Flux density will become [BSNL TTA

2016]a) 10−4 Wb/m²

b) 10+4 Wb/m²

c) 10−2 Wb/m²

d) 𝟏 wb/m²

7. Magnetostriction is a phenomenon of: [FCI 2015]

a) Generation of electricity in ferromagnetic

materials

b) Generation of magnetism in ferromagnetic

materials

c) Change in permeability of ferromagnetic

materials during magnetization

d) Change in physical dimension of ferromagnetic

materials during magnetization

8. Which of the following statement is correct? [ESIC

JE Electrical 2016]

a) The magnetic Flux inside an exciting coil is lower

than its outside surface

b) The magnetic Flux inside an exciting coil is zero

c) The magnetic Flux inside an exciting coil is

greater than its outside surface

d) The magnetic Flux inside an exciting coil is same

as on its outside surface

9. A coil having 90 turns is connected to a 120 V, 60

Hz source. If the effective value of the magnetizing

current is 4 A, then calculate the value of

inductance of the coil. [Jammu & Kashmir JE

electrical 2016]

a) 79.6 mH

b) 121.2 mH

c) 32.2 mH

d) 83.16 mH

10. According to Biot–Savart’s laws the magnetic

field at a point due to incremental element of length

dl carrying a current is. [Jammu & Kashmir JE

Elctrical]

a) Inversely proportional to the current carried by

the element

b) Directly proportional to the current carried by the

element

c) Directly proportional to the square of the

distance

d) Inversely proportional to the length of the

element

11. In Fleming’s right hand rule the middle finger

indicates the direction of: [LMRC JE Electrical 2016]

a) force on a current carrying conductor

b) dynamically induced emf in a conductor

c) magnetic field

d) motion given to the conductor

12. Which of the following does not pertain to theequation 𝛻. B = 0? [Coal India Ltd. Electrical 2017]

a) Single magnetic pole cannot exist

b) There are no sinks and sources for magnetic field

c) Magnetic field is perpendicular to the electric

field

d) Magnetic field is solenoidal

13. The electric and magnetic fields are: [Coal India

Ltd. Electrical 2017]

a) two distinctly separate and isolated phenomena

b) two parts of one unique phenomena

c) two conflicting phenomena, one suppressing the

other

d) two sequential phenomena, with a retardation

effect between the two fields

14. The dielectric strength of rubber is 30000 V/mm

at frequency of 50 Hz. What is the thickness of

insulation required on an electrical conductor at 33

kV to sustain the breakdown? [UPPCL AE Electrical]

a) 0.825 cm

b) 0.8 mm

c) 1.0 cm

d) 1.1 mm

15. A cast steel electromagnet has an air gap

length of 0.3 cm. Find the ampere–turns for the air

gap to produce a Flux density of 0.7 Wb/m² in the

air gap. [SSC JE Electrical 2017]

a) 2100 AT

b) 1671 AT

c) 1447 AT

d) 167 AT

16. When the total charge in a capacitor is doubled,

the energy stored [APSPDCL-14]

a) remains the same

b) is halved

c) is doubled

d) is quadrupled

17. The electric field intensity due to an infinite

plane sheet of charge is [UPRVUNAL AE Electrical

2014]

a) Inversely proportional to the perpendicular

distance of the field point P from the plane sheet

b) Directly proportional to the perpendicular

distance of the field point P from the plane sheet

c) Independent of the location of the field point P

d) None of the other options

18. Capacitance of a capacitor [BSNL TTA 2016]

a) Increases with increases in overlapping Area of

plates

b) Increases with increases in relative permittivity of

the dielectric

c) Increases with decreases in distance between

the plates

d) All of these

19. An air-filled parallel plate capacitor made of

square plates, each 10cm×10cm, has a

capacitance C. If the plates are reduced to 2.5

cm×2.5cm, what would be the new capacitance?

[BSNL TTA JE 2013]

a) C/4

b) C/8

c) C/16

d) C/32

20. In a parallel plate capacitor, a dielectric slab is

introduced, the potential difference between plates

will? [SSC JE Electrical 2017]

a) decrease

b) remain the same

c) increase

d) becomes zero

21. When a dielectric is placed in an electric field,

the field strength......... . [SSC JE Electrical 2017]

a) Increases

b) Decreases

c) Remain unchanged

d) Reduces to zero

UPPSC AE - 2020

SSC JE-2019

Benefits

Personalized Learning: -

Regular PDF update

(28) In a steam power plant…………heats the feed water on its way to the boiler by

delivering heat from the flue gases: -

(A) Superheater (B) Economizer

(B) Preheater (D) Turbine

(29) Power generation of thermal power plants is based on: -

(A) Rankine cycle

(B) Otto cycle

(C) Diesel cycle

(D) Carnot cycle

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