Quiz: Electrical Engineering 4 June 2020

Quiz: Electrical Engineering
Exam: UPPSC-AE
Topic: Single phase induction motor

Each question carries 1 mark.
Negative marking: 1/4 mark
Time: 10 Minute

Q1. Speed higher than synchronous speed can be held by
(a) Line voltage control
(b) rotor slip power control
(c) rotor resistance control
(d) frequency control

Q2. In a slip power recovery scheme for 3 phase induction motor, if slip power is
(a) returned to supply, constant power drive is obtained
(b) added to the main shaft, constant power drive is obtained
(c) subtracted from the main shaft, constant torque drive is obtained
(d) obtained from the supply, constant torque drive is obtained

Q3. During plugging of an induction motor
(a) phase sequence is reverted
(b) a dc source is connected to stator
(c) one phase is open circuited
(d) power is fed back to mains

Q4. In dynamic breaking of 3 phase induction motors
(a) the supply terminals of any two stator phases are interchanged
(b) any two stator terminals are earthed
(c) the stator terminals are switched over to a dc source from the ac supply
(d) a dc voltage is injected in the rotor circuit

Q5. The stator of 2/4 pole changing cage motor is initially wound for 2 poles. The reconnection of the stator winding to 4-pole through a changeover switch, while the motor is running would result in
(a) constant torque drive
(b) constant hp drive
(c) plugging to stand still
(d) regenerative breaking to half the original speed.

Q6. A squirrel cage induction motor runs slow, probably cause could be
(a) low voltage
(b) short stator coil
(c) one phase open
(d) Any of the above

Q7. Three phase induction motor should preferably be mounted on
(a) wooden structure
(b) PVC platform
(c) solid concreate foundation
(d) none of the above

Q8. The factors to be considered in the selection of motors is/are
(a) voltage rating of motor
(b) kW output rating of motor
(c) speed and frame enclosure size
(d) all of the above

Q9. Induction generators deliver power at
(a) leading power factor only
(b) lagging power factor only
(c) leading as well as lagging power factor
(d) unity power factor only

Q10. What is the rotor copper loss of a 3 phase 550 volts, 50 Hz, 6 pole induction motor developing 4.1 kW at the shaft with mechanical loss of 750 W T 970 rpm?
(a) 275 W
(b) 150 W
(c) 100 W
(d) 250 W

Solutions
S1. Ans. (b)
Sol. rotor slip power control are best suited for mentioned situation.

S2. Ans. (b)
Sol. added to the main shaft, constant power drive is obtained

S3. Ans. (a)
Sol. phase sequence is reverted for desired result quickly.

S4. Ans. (c)
Sol. the stator terminals are switched over to a dc source from the ac supply

S5. Ans. (d)
Sol. regenerative breaking to half the original speed.

S6. Ans. (d)
Sol. All the condition result in slow running of motor. Over load and open stator coil may be additional reason for slow running.

S7. Ans. (d)
Sol. solid concreate foundation

S8. Ans. (d)
Sol. All the mentioned factors should be considered.

S9. Ans. (a)
Sol. Induction generators deliver power at leading power factor only.

S10. Ans. (b)
Sol. Synchronous speed,
Ns = 120f/P
=(120×50)/6 = 1000 rpm
=(N_s-N)/N_s = (1000-970)/1000
=0.03
Mechanical Power developed,
Pmech = Shaft power + mechanical loss
=4100+750 W
= 4850 W
Rotor copper loss,
= s/(1-s) ×4850 W
= 150 W

Quiz: Electrical Engineering 3 June 2020

Quiz: Electrical Engineering
Exam: UPSSSC JE
Topic: Instruments & Measurements

Each question carries 1 mark.
Negative marking: 1/4 mark
Time: 10 Minute

Q1. For controlling the vibration of the disc of an ac energy meter, damping torque is produced by
(a) eddy current
(b) chemical effect
(c) electrostatic effect
(d) magnetic effect

Q2. Creep error may occur in induction type energy meter due to
(a) incorrect position of brake magnet
(b) incorrect adjustment of position of shading band
(c) over voltage across voltage coil
(d) increase in temperature

Q3. Holes are drilled on the opposite sides of the disc of an induction type energy meter to
(a) avoid creep on no load
(b) balance the disc
(c) dissipate the energy due to eddy current
(d) increase the deflecting torque

Q4. Which of the following is the main cause of creeping in the induction type energy meter?
(a) friction compensation
(b) lag/lead compensation
(c) overload compensation
(d) braking torque producing system

Q5. In a single-phase induction type energy meter, the lag adjustment is done to ensure that
(a) current coil flux lags the applied voltage by 90°
(b) pressure coil flux lags the applied voltage by 90°
(c) pressure coil flux is in phase with the applied voltage.
(d) current coil flux lags the pressure coil flux by 90°

Q6. Which of the following method is used for the measurement of high resistance?
(a) Carey Foster’s bridge method
(b) substitution method
(c) loss of charge method
(d) Potentiometer method

Q7. The sensitivity of Wheatstone bridge depends upon
(a) galvanometer voltage sensitivity
(b) galvanometer resistance
(c) bridge supply voltage
(d) all of the above

Q8. Wagner’s earthing device is used in ac bridge for
(a) shielding the bridge elements
(b) eliminating the stray electrostatic field effect
(c) eliminating the effect of earth capacitance
(d) eliminating the effect of inter-component capacitances

Q9. What should be the main characteristic of the null detector in a bridge measurement?
(a) accuracy
(b) precision
(c) Sensitivity
(d) Resolution

Q10. The dielectric loss of capacitor can be measured by which of the following?
(a) Wien bridge
(b) Owen bridge
(c) Shearing bridge
(d) Maxwell bridge

Solutions

S1. Ans. (a)
Sol. Eddy current

S2. Ans. (c)
Sol. Overvoltage across voltage coil

S3. Ans. (a)
Sol. To avoid creep on no load.

S4. Ans. (a)
Sol. Friction compensation is the right option.

S5. Ans. (b)
Sol. pressure coil flux lags the applied voltage by 90°

S6. Ans. (c)
Sol. Loss of charge method is used to calculate high resistance.

S7. Ans. (d)
Sol. All factors are responsible for sensitivity of Galvanometer

S8. Ans. (c)
Sol. eliminating the effect of earth capacitance

S9. Ans. (d)
Sol. Resolution should be the main characteristic.

S10. Ans. (d)
Sol. Shearing bridge

SSC JE Exam Dates Announced; Check Details

Staff Selection Commission, SSC, is a statutory body operating under the aegis of the central government of India and is responsible for the selection of suitable candidates for various vacancies available with different ministries, departments, and undertakings. In order to select the most suitable candidates, SSC conducts various recruitment rives every year, in which hundreds of thousands of candidates participate every year. This year, the recruitment drives of SSC have been delayed due to the nationwide lockdown prompted by the Coronavirus pandemic. But finally, things are back on track.

As per the latest reports from SSC, the new dates for SSC JE Exam 2020 have been announced on the official website of SSC. As per the notification, the SSC JE Exam 2020 will now be conducted from 1st September 2020 to 4th September 2020 across multiple examination centres in the country. The SSC JE Exam 2020 will be conducted in the online mode. Previously, the exam was scheduled to be conducted from 30th March 2020 to 2nd April 2020 but had t be postponed due to the Coronavirus pandemic and the ensuing nationwide lockdown.

 

SSC JE Exam 2020: Admit Card

Candidates who have completed their online applications for SSC JE Exam 2020 and have paid the requisite fees as well, will only be allowed to appear for the SSC JE Exam 2020. The admit cards will be available for download from the official website of SSC at least one week prior to the exam. Candidates must, therefore, log-on to the official website @ www.ssc.nic.in when the admit card is released, download it, and take a printout to be carried along on the day of the examination. Details regarding the examination venue, timings, and other important information will be mentioned on the admit card itself. Any candidates appearing for the SSC JE Exam 2020 without the admit card, will not be allowed to appear for the examinations. It is also mandatory to bring along a valid id proof along with the admit card on the day of the SSC JE Exam 2020.

 

SSC JE Exam 2020: Important Dates

Candidates who will be appearing for the SSC JE Exam 2020, must note the below mentioned important dates to avoid any confusion later on.

S. No.     Event                                                           Date
1             Original dates for SSC JE Exam 2020      30th Mach 2020 to 2nd April 2020
2             New dates for SSC JE Exam 2020             1st September 2020 to 4th September 2020
3             SSC JE Exam 2020 Admit Card                 Last week of August
4             SSC JE Exam 2020 Paper I                         1st September 2020 to 4th September 2020
5             SSC JE Exam 2020 Paper II                          To be announced

Quiz Electronics Engineering 2 June 2020

Quiz Electronics Engineering
Exam: NIC
Topic: Miscellaneous
Date: 02/06/2020

Each Question carries 1 Mark
Negative Marking: 1/4
Time: 10 Minutes

Q1. A class member declared protected in Java becomes member of subclass of which type?
(a) Public Member
(b) Protected Member
(c) Private Member
(d) Static Member

Q2. How many full adders are required to construct an m-bit parallel adder?
(a) m
(b) m – 1
(c) m/2
(d) m + 1

Q3. Which type of traversal of binary search tree outputs the value in sorted order?
(a) Pre-order
(b) In-order
(c) Post-order
(d) Level-order

Q4. A positive AND gate is also a negative
(a) NAND gate
(b) OR gate
(c) AND gate
(d) NOR gate

Q5. Events A and B are mutually exclusive and have non-zero probability. Which of the following statement is TRUE?
(a) P(AUB) = P(A) + P(B)
(b) P(B’) > P(A)
(c) P(A∩B) = P(A)P(B)
(d) P(B’) < P(A)

Q6. Assume transaction A holds a shared lock R. If transaction B also requests for a shared lock on R. It will
(a) result in deadlock situation
(b) immediately be granted
(c) immediately be rejected.
(d) None of the above

Q7. Web links are stored within the page itself and when you wish to jump to the page that is linked, we select the hotspot or anchor. This technique is called
(a) Hypertext
(b) Hypermedia
(c) both (a) & (b)
(d) Anchoring

Q8. Which of the following is not a form of main memory?
(a) Instruction opcode
(b) Instruction register
(c) Instruction cache
(d) Translation look-aside buffer

Q9. The number of the edges in a regular graph of degree ‘d’ and ‘n’ vertices is
(a) Maximum of n, d
(b) n + d
(c) nd
(d) nd/2

Q10. Synthesized attribute can easily be simulated by an
(a) LL grammar
(b) ambiguous grammar
(c) LR grammar
(d) None of the above

 

 

SOLUTIONS

S1. Ans.(c)
Sol. A class member which is declared protected from before becomes the Private member of subclass.

S2. Ans.(a)
Sol. For n-bit adder, we require-
(a) (n-1) FA and 1 HA ; or
(b) n FA ; or
(c) (2n-1) HA & (n-1) OR gate.

S3. Ans.(d)
Sol.
(a) In Pre-order , the Root node is visited first, then the Left subtree and at last Right Subtree.
(b) In-order, Left Subtree is visited first , then the Root node, and at last Right Subtree.
(c) Post-order, at first Left Subtree, then Right Subtree and finally Root node.
(d) Level-order is breadth first traversal for the tree.

S4. Ans.(b)
Sol. Positive AND gate has input A, B and output AB.
Negative OR gate will have inverter at both inputs and 1 Output.
So, Output at the negative OR gate is
(A ̅+B ̅ ) ̅ = (AB) ̅ ̅ = AB = Positive AND gate output

S5. Ans.(a)
Sol. By principle of inclusion and exclusion, we get
P(AUB) = P(A) + P(B) + P(A∩B)
In Mutually exclusive condition –
P(A∩B) = 0

So, P(AUB) = P(A) + P(B)

S6. Ans.(b)

immediately be granted

S7. Ans.(c)

Sol. Both (a) and (b)

S8. Ans.(a)
Sol. Instruction opcode tells about what operation to be performed. Excluding it, all are form of a main memory.

S9. Ans.(d)
Sol. Given:
Number of vertices = n
Degree of each vertices or number of neighbours of each vertices = d
So, Total edges = nd/2

S10. Ans.(c)
Sol. Both Synthesized attribute and LR grammar are evaluated in bottom up method. So, these can be simulated easily.

Quiz: Electrical Engineering 1 June 2020

Quiz: Electrical Engineering
Exam: UPSSSC JE
Topic: Measurement and measuring instrument
Each question carries 1 mark.
Negative marking: 1/4 mark
Time: 10 Minute

Q1. Horizontally mounted moving iron instruments employ
(a) eddy current damping
(b) air friction damping
(c) fluid friction damping
(d) electromagnetic damping

Q2. The deflecting torque of moving iron instrument is
(a) I^2 dL/dθ
(b) 1/2 I^2 dL/dθ
(c) I dL/dθ
(d) 1/2 I dL/dθ

Q3. Hysteresis error, in moving iron instruments, may be reduced by using
(a) mumetal or permalloy
(b) stainless steel
(c) silver coating
(d) high speed steel

Q4. A spring controlled moving iron voltmeter draws a current of 1 mA for full scale value of 100 V. If it draws a current of 0.5 mA the meter reading is
(a) 25 V
(b) 50 V
(c) 100 V
(d) 200 V

Q5. Moving coil permanent magnet instrument can be used for the measurement of
(a) AC and DC
(b) AC only
(c) DC only
(d) half wave rectified DC

Q6. An advantage of PMMC instrument is that it
(a) is free from friction error
(b) has high torque to weight ratio of moving parts
(c) has low torque to weight ratio
(d) can be used on both AC and DC

Q7. The term artificial aging in instrument is associated with
(a) springs
(b) permanent magnets
(c) controlling torques
(d) both (a) and (b)

Q8. A PMMC voltmeter is connected across a series combination of a dc voltage source V1 = 2V and an ac voltage source V2(t)= 3 Sin (4t) volts. The meter reads
(a) 2 V
(b) 5 V
(c) (2+√3/2)V
(d) √17/2 V

Q9. Which of the following meters does not exhibit square law response?
(a) Moving coil
(b) Moving iron
(c) Electrodynamometer
(d) hot wire instrument

Q10. Which of the following instrument is commonly used to measure primary current of a transformer connected to mains?
(a) Electrostatic meter
(b) Current transformer
(c) Moving coil type meter
(d) Moving iron meter

Solutions
S1. Ans. (b)
Sol. air friction damping

S2. Ans. (b)
Sol. The correct relation for torque in moving iron is 1/2 I^2 dL/dθ.

S3. Ans. (a)
Sol. mumetal or permalloy

S4. Ans. (a)
Sol. Deflection, θ∝I^2
So, V∝I^2
V2 = V1 ((I^2 2)/(I^2 1)), putting the value in equation we get as the result
V2 = 25 V
S5. Ans. (c)
Sol. Moving coil permanent magnet instrument can be used for the measurement of DC only.

S6. Ans. (b)
Sol. has high torque to weight ratio of moving parts.

S7. Ans. (d)
Sol. Both spring and controlling torque are associated with term aging.

S8. Ans. (a)
Sol. The average value of ac current is zero so the instrument will measure 2 V .

S9. Ans. (a)
Sol. Moving iron

S10. Ans. (d)
Sol. Moving iron meter

Quiz Electronics Engineering 30 may 2020

Quiz Electronics Engineering

Exam: NIC

Topic: Miscellaneous

Date:  30/05/2020

 

Each Question carries 1 Mark

Negative Marking:  1/4

Time: 10 Minutes

 

 

Q1. ……. feature allows you to optimize your system and capture all possible transactions.

(a) scalability

(b) reliability

(c) elasticity

(d) None of the above

 

 

Q2. Out of given options, which one monitors user activity on internet and transmit that information in background to someone else?

(a) Trojan Horse

(b) Spyware

(c) Adware

(d) None of the above

 

 

Q3. Overlaying

(a) is transparent to the user

(b) requires use of a loader

(c) allows larger programs, but requires more effort

(d) is mostly used on large computers

 

 

Q4. What does XHTML stands for?

(a) Extra Hyperlinks and text Markup Language

(b) Extreme Hypertext Markup Language

(c) Extended Hypertext Mark Up Language

(d) Extensible Hypertext Markup language

 

 

Q5. What are SSL and TLS?

(a) Internet protocols

(b) Data Link Layer

(c) Cryptographic Protocol

(d) Internet Layer

 

 

Q6. Management of software development is dependent on

(a) People

(b) Product

(c) Process

(d) All of the above

 

 

Q7. IPv6 supports which of the following addressing modes?

(a) Unicast addressing

(b) Multicast addressing

(c) Anycast addressing

(d) All of them

 

 

Q8. _____________ enables the migration of the virtual image from one physical machine to another.

(a) visualization

(b) virtualization

(c) migration

(d) virtual transfer

 

 

Q9. Antivirus signatures are created using which of the following?

(a) Decryption Algorithm

(b) Encryption Algorithm

(c) Hashes

(d) CRC

 

 

Q10. In the relational model, cardinality is termed as:

(a) A number of attributes.

(b) A number of tuples.

(c) A number of tables.

(d) A number of constraints.

 

 

SOLUTIONS

 

S1. Ans.(c)

Sol. Elasticity is the degree to which a system is able to adapt to workload changes by provisioning and de-provisioning resources in an autonomic manner. It has the ability to right-size resources as required.

 

 

S2. Ans.(b)

Sol. Spyware is a software that is installed on your computer directly or indirectly. It monitors different programs, internet activity secretly while running in background of your computer.

 

 

S3. Ans.(a)

Sol. Overlaying is the process of transferring a block of program code or other data into internal memory, replacing what is already stored. This technique allow programs to be larger than the computer’s main memory.

 

 

S4. Ans.(d)

Sol.  Extensible Hypertext Markup Language (XHTML) is part of the family of XML markup languages.

 

 

S5. Ans.(c)

Sol.

  • Secure Sockets Layer (SSL) is a networking protocol designed for securing connections between web clients and web servers over an insecure network like internet.
  • TLS is Acronym of Transport Layer Security.

Both are cryptographic protocols designed to provide communications security over a computer network.

 

 

S6. Ans.(d)

All of the above

 

S7. Ans.(d)

Sol. IPv6 supports unicast, multicast and anycast addressing modes.

 

S8. Ans.(b)

Sol. Virtualization enables the migration of the virtual image from one physical machine to another. Virtualization allows to share a single physical instance of a resource or an application among multiple customers and organizations at one time. It helps in optimization by sharing data to different machines.

 

 

S9. Ans.(c)

Sol. An Antivirus Signature is a set of unique data or bits of code for its identification. Anti-virus software uses the virus signature to scan for the presence of malicious code.

 

 

S10. Ans.(b)

A number of tuples.

Quiz: Electrical Engineering 30 May 2020

Quiz: Electrical Engineering
Exam: NLC
Topic: Network theorems

Each question carries 1 mark.
Negative marking: 1/4 mark
Time: 10 Minute

Q1. Which of the following will not be affected due to change in R?
(a) Bandwidth
(b) Q
(c) Resonant frequency
(d) None

Q2. The resonant frequency of an RLC series circuit is 1.5 MHz with the resonating capacitor of 150 pF. The bandwidth is 10 kHz. The effective value of the resistor is
(a) 16.3 Ω
(b) 9.5 Ω
(c) 7.4 Ω
(d) 4.7 Ω

Q3. A parallel circuit is said to be in resonance when the admittance is purely
(a) capacitive
(b) inductive
(c) susceptive
(d) conductive

Q4. Consider the following statement:
If a high Q parallel resonant circuit is loaded with a resistance
The circuit impedance reduces
The resonant frequency remains the same
The bandwidth reduces
Which of the above statements is/are correct?
(a) 3 only
(b) 2 only
(c) 1 only
(d) 1,2 and 3

Q5. A parallel resonant circuit can be employed
(a) as a high impedance
(b) to reject a small band of frequencies
(c) to amplify certain frequencies
(d) both (a) and (b)

Q6. What is the locus of the tip of the voltage phasor across R in a series RLC circuit?
(a) A Parabola
(b) An ellipse
(c) A circle
(d) A rectangular hyperbola

Q7. A non-ideal voltage source Vs has an internal impedance of Zs. if a purely resistive load is to be chosen that maximizes the power transferred to the load, its value must be
(a) 0
(b) real part of Zs
(c) magnitude of Zs
(d) complex conjugate of Zs

Q8. A capacitor is charged to a voltage of 440V and has a resistance of 35 ohm. Calculate the initial value of charging current.
(a) 100 A
(b) 0
(c) infinity
(d) 200 A

Q9. The total charge entering the terminal of an element is given by;
q = (6t² – 12t) mC
(a) 36 mA
(b) 24 mA
(c) 102 mA
(d) 72 mA

Q10. A load is connected to a circuit. At the terminals to which the load is connected, R_Th = 10 Ω and V_Th = 60 V. The maximum power supplied to the load is
(a) 400 W
(b) 1600 W
(c) 700 W
(d) 900 W

Solutions
S1. Ans. (c)
Sol. Frequency won’t be affected.

S2. Ans. (d)
Sol. Q =(resonance frequency)/bandwidth
=(ωr L)/R= 1/(ωr RC)
Value of R can be computed as R = 4.7 Ω
S3. Ans. (d)
Sol.
S4. Ans. (d)
Sol. All the statements are correct.
S5. Ans. (d)
Sol. A parallel resonant circuit can be employed as both of following
as a high impedance
to reject a small band of frequencies

S6. Ans. (c)
Sol. A circle

S7. Ans. (c)
Sol. magnitude of Zs

S8. Ans. (b)
Sol. Initially, there’s 0V voltage in a capacitor. As the capacitor charges, the voltage increases. Since a voltage is proportional to current by ohm’s law, initial current is also equal to zero.

S9. Ans. (a)
Sol. Sol. Current, i=dq/dt=d/dt (q)=d/dt (6t^2-12t)=(12t-12) mA
At t = 4s, i = 12 × 4 – 12 = 48 – 12 = 36 mA

S10. Ans. (d)
Sol. Under maximum power transfer, R_L-R_Th and voltage across R_L=V_Th/2.
∴P_(max.)=(V_Th/2)²/R_Th =(60/2)²/10=900 W

SSC JE Foundation batch for Civil, Electrical and Mechanical

The SSC JE Exam is one of the most competitive examinations in the country which is attempted by hundreds of thousands of students aspiring for a government job in the engineering stream. Due to the Coronavirus pandemic, the SSC JE 2020 Exam has been postponed several times. Right now, all the candidates are waiting for the declaration of the new dates for the exam, which might be announced after the review meeting on 1st June 2020.

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Quiz Electronics Engineering 29 May 2020

Quiz Electronics Engineering
Exam: NIC
Topic: Miscellaneous
Date: 29/05/2020

Each Question carries 1 Mark
Negative Marking: 1/4
Time: 10 Minutes

Q1. If the connection of two-port is such that the transmission matrix of the overall network is the product of the transmission matrices of the individual networks, what type of connection is it?
(a) Series Connection
(b) Parallel Connection
(c) Cascade Connection
(d) None of the above

Q2. A junction FET can be used as a Voltage Variable Resistor
(a) well below pinch-off condition
(b) beyond pinch-off voltage
(c) at pinch-off voltage
(d) for any value of V_DS

Q3. If 225_Y = 165_8, find the value of radix base.
(a) 11
(b) 8
(c) 9
(d) 7

Q4. Recursion uses more memory space than iteration because
(a) it uses stack instead of queue
(b) every recursive call has to be stored
(c) both (a) & (b)
(d) None of the above

Q5. If P(A ∩ B) = P(A)P(B), then events A and B are called
(a) independent
(b) dependent
(c) exhaustive
(d) None of the above

Q6. A balance factor in AVL tree is used to check
(a) what rotation to make
(b) if all child nodes are at same level
(c) when the last rotation occurred.
(d) if the tree is unbalanced.

Q7. In a compiler, keywords of a language are recognized during
(a) parsing of the program
(b) the code generation
(c) the lexical analysis of the program
(d) dataflow analysis

Q8. Which one of the following is not an approach to compute the Minimum spanning tree in a weighted graph?
(a) Kruskal
(b) Prim’s
(c) Boruvka’s
(d) Dijkstra’s

Q9. The addressing mode used in the instruction PUSH B is
(a) direct
(b) register
(c) register indirect
(d) immediate

Q10. Which of the following is the internal memory of the system(computer)?
(a) CPU register
(b) Cache
(c) Main memory
(d) All of the above

SOLUTIONS

S1. Ans.(c)

S2. Ans.(a)
Sol. In Triode region which is below the Pinch-off voltage the drain to source resistance is controlled by bias voltage(V_GS). Therefore, JFET can be used as Voltage Variable Resistor.

S3. Ans.(d)
Sol.
225_Y = 2 × Y^2 + 2 × Y^1 + 5 × Y^0 = 2Y^2 + 2Y^1 + 5
165_8 = 1 × 8^2 + 6 × 8^1 + 5 × 8^0 = 64 + 48 + 5 = 117
Now, 225_Y = 165_8
⇒ 2Y^2 + 2Y^1 + 5 = 117
⇒ 2Y^2 + 2Y^1 = 117 – 5 = 112
⇒ 2Y^2 + 2Y^1 – 112 = 0
So, Y = +7 & -8
Radix base cannot be negative.

Therefore, the value of radix base is 7.

S4. Ans.(c)
Sol. Recursion uses more memory compared to iteration because every time the recursive function is called, the function call is stored in stack.

S5. Ans.(a)
Sol. Two events A and B are said to be independent if the occurrence of one event has does not affect the probability that the other event will occur. If two events are independent then
P(A∩B) = P(A)P(B)

S6. Ans.(d)
Sol. AVL trees are height balancing binary search tree. It checks the difference of the height of the left and the right sub-trees and assures that it is not more than 1. This difference is called the Balance Factor. So. with the help of balance factor we check if tree is balanced or not.

S7. Ans.(c)
Sol. A keyword can also be called as Tokens. During the lexical analysis of the program a sequence of characters are converted into a sequence of tokens. Keywords are usually first recognized during lexical analysis in order to make parsing easier. Parsers are implemented by writing context-free grammars of tokens rather than of lexemes so it becomes easier to build parser after keywords are recognized.

S8. Ans.(d)
Sol. Prim’s, Kruskal’s and Boruvka’s algorithm are a Greedy algorithm. These all are used to compute the Minimum spanning tree in a weighted graph.
Prim’s Algorithm is used to find Minimum Spanning Tree (MST).
Dijkstra’s Algorithm is used to find the shortest path from source to all the other nodes in a weighted graph.

S9. Ans.(b)
Sol. In Register addressing mode, the operand is hold in the register memory mentioned in the instruction. So, In PUSH B Register addressing mode is used.

S10. Ans.(d)
Sol. All three are the internal memory of the system. CPU register is the smallest and Main memory is the largest internal memory. Registers are the smallest and the fastest memory in a computer. It hold instructions that are currently processed by the CPU.

PGCIL Powergrid Recruitment Notification 2020 Out, Apply For 114 Apprentice Post @powergridindia.com

Powergrid Corporation of India Ltd. is one of the most reputed public sector undertakings of India operating in the energy sector. In order to support the rising demand across the country, PGCIL conducts various recruitment drives periodically, which attracts the attention of numerous applicants. There is an important update for candidates who are interested in pursuing a career with the Powergrid Corporation of India Ltd. As per the latest notification from the organisation, applications have been invited from interested candidates for 114 vacancies available for the apprentice post under PGCIL Recruitment 2020

 

This recruitment drive is being organised to fill 114 vacancies available across various trades in the western region of the country comprising Madhya Pradesh, Maharashtra, Goa, and Chhattisgarh. Candidates who meet the eligibility criteria of the PGCIL Recruitment 2020 and are interested in the available vacancies must log-on to the official website of PGCIL Recruitment 2020, i.e. www.powergridindia.com and complete their applications online. The online application process has already commenced and will continue till 14th June 2020. So, the interested candidates must complete their online application process as soon as possible, without waiting till the last minute.

PGCIL Recruitment 2020: Vacancies Details

Candidates who are interested in PGCIL Recruitment 2020 must make a note of the below mentioned important information: –

The details of the available vacancies under PGCIL Recruitment 2020 is as follows: –

o   Assistant (Human Resource) – 4 Vacancies

o   Diploma in Electrical Engineering – 23 Vacancies

o   Graduate in Civil Engineering – 11 Vacancies

o   Executive (Human Resource) – 5 Vacancies

o   Graduate in Electrical Engineering – 69 Vacancies

o   Diploma in Office Management – 2 Vacancies

 PGCIL Recruitment 2020 Salary

The details of the stipend payable under PGCIL Recruitment 2020 is as follows: –

o   For the post of Graduate in Electrical Engineering – Rs. 15,000

o   For the post of Diploma in Office Management – Rs. 12,000

o   For the post of Assistant (Human Resource) – Rs. 12,000

o   For the post of Graduate in Civil Engineering – Rs. 15,000

o   For the post of Executive (Human Resource) – Rs. 15,000

o   For the post of Diploma in Electrical Engineering – Rs. 12,000

PGCIL Recruitment 2020: Important Dates

Candidates must note the below mentioned important dates for PGCIL Recruitment 2020: –

–          Publication of the notification        –       22nd May 2020

–          Application process commences    –       22nd May 2020

–          Application process ends                –       14th June 2020

 

 PGCIL Recruitment 2020 Eligibility

Only those candidates are eligible for application under PGCIL Recruitment 2020 who have completed their final year examinations less than 2 years before the notification being published. Candidates must log-on to the official website of PGCIL Recruitment 2020 to complete their applications before 14th June 2020. Once the application window is closed, no new applications will be accepted under PGCIL Recruitment 2020.

How To Apply For PGCIL Powergrid Apprentice Recruitment?

Click on  ‘Click Here To Apply

Register yourself per their educational qualifications, and Enter BOAT\RDAT Registration ID’ to register yourself in the NATS portal.

Then click on the ‘Submit’ option.

Finally, fill in your personal details.

JUVNL Recruitment 2020: 2100 new vacancies to be available at Jharkhand Urja Vikas Nigam

The nationwide lockdown prompted by the Coronavirus pandemic has affected each and every sector of the economy. All recruitment drives have been put on hold by the government agencies and departments due to the prevailing uncertainty. This has come as a source of disappointment for candidates who were looking to participate in the upcoming recruitment drives. But finally, things have started moving, and the agencies are resuming their recruitment drives.

There is an important update for candidates residing in Jharkhand and looking for a career with the Jharkhand Urja Vikas Nigam. As per the latest updates issued by the state government, the Jharkhand Urja Vikas Nigam will initiate a recruitment drive to fill 2100 new vacancies as soon as the lockdown ends. These recruitments will be made across different subsidiaries of the Jharkhand Urja Vikas Nigam.

Candidates who are interested in applying for the vacancies available under JUVNL Recruitment 2020 must wait for further announcements regarding the upcoming recruitment drive. Candidates are advised to regularly check the official website of JUVNL Recruitment 2020 for important updates and information.

 

JUVNL Recruitment 2020: Need to advertise the vacancies

The Jharkhand Urja Vikas Nigam is facing a severe shortage of engineers and other qualified personnel due to multiple retirements in the last few weeks. As a matter of fact, presently, there is one Chief Engineer rank officer in the department. Lack of adequate employees is severely hampering the functioning of the essential functions of the department. In addition to Chief Engineer, the department is facing a shortage of Junior Engineers, Assistant Engineers, Switchboard operator and lineman as well. It is becoming difficult for the Jharkhand Urja Vikas Nigam to continue its operations and maintenance tasks due to lack of qualified personnel.

 

JUVNL Recruitment 2020: Details of the vacancies

As per the details shared by the Jharkhand Urja Vikas Nigam, the JUVNL Recruitment drive will be conducted for the 2100 vacancies available with the department. The details of the vacancies are as follows: –

S. No. Post Vacancies
1 Assistant Electrical Engineer 250 vacancies
2 Junior Engineer 450 vacancies
3 Lineman 750 vacancies
4 Switch Board Operator 300 vacancies
5 Accounting Clerk 350 vacancies

 

The work for preparing the guidelines for the JUVNL Recruitment 2020 has already commenced, but no formal announcement has been made by the government. It is expected that when the fourth phase of lockdown ends, only then the recruitment process under JUVNL Recruitment 2020 commence.

 

 

Quiz Electronics Engineering 28 May 2020

Quiz Electronics Engineering
Exam: NIC
Topic: Miscellaneous
Date: 28/05/2020

Each Question carries 1 Mark
Negative Marking: 1/4
Time: 10 Minutes

Q1. The average search time of hashing, with linear probing will be less if the load factor
(a) equals one
(b) is far greater than one
(c) is far less than one
(d) none of the above

Q2. During software development, which factor is most crucial?
(a) Product
(b) Process
(c) People
(d) Project

Q3. Consider the following sorting algorithms. Which of them perform in least time in the worst case?
(a) Quick sort
(b) Heap sort
(c) Merge sort
(d) both (b) and (c)

Q4. A full binary tree with n non leaf nodes contain.
(a) log2n nodes
(b) n+1 nodes
(c) 2n+1 nodes
(d) 2n nodes

Q5. A relation scheme is in ……… if it is in the 1 NF and if all non-prime attributes are fully functionally dependent on the relation key(s).
(a) First Normal Form
(b) Second Normal Form
(c) Boyce Codd Normal Form
(d) Fourth Normal Form

Q6. Which of the following operator(s) cannot be overloaded?
(a) ?: (conditional)
(b) Size of (object size information)
(c) .*(member selection with pointer to member)
(d) All of the above

Q7. Which one of these are characteristic of RAID 5?
(a) Distributed parity
(b) Double parity
(c) Hamming code parity
(d) Dedicated party

Q8. TRUNCATE statement in SQL is a-
(a) DML statement
(b) DDL statement
(c) DCL statement
(d) All of these

Q9. A PLA can be used
(a) as a micro processor
(b) as a dynamic memory
(c) to realise a sequential logic
(d) to realise a combinational logic

Q10. Which of the following memories is directly accessible by the CPU?
(a) RAM
(b) Hard Disk
(c) Magnetic Type
(d) DVD

SOLUTIONS

S1. Ans.(c)
Sol.
Load Factor = (total number of records currently present)/(total number of records that can be present)

The average search time of hashing, with linear probing will be less if the load factor is far less than one. Load factor less than 1 is possible when free space is more. Free space more means less collision so searching time will be less.

S2. Ans.(c)
Sol. The software development is dependent upon four factors. Those are People, Product, Process and Project. Software development requires good managers. The manager who can understand the requirements of people. Hence , people are the most crucial factor during software development.

S3. Ans.(d)
Sol.
Worst case time complexity of Quick sort = O(n2,) when input is already sorted or reverse sorted.
Worst case time complexity of Heap sort = O(nlogn).
Worst case time complexity of Merge sort = O(nlogn).

S4. Ans.(c)

S5. Ans.(b)
Sol. A database is in Second Normal Form if it satisfies the following conditions:
It is in First Normal Form
All non-key attributes are fully functional dependent on the primary key

S6. Ans.(d)
Sol. Operators which cannot be overloaded are :
1. ?: (conditional)
2. .(member selection)
3. .*(member selection with pointer to member)
4. :: (scope resolution)
5. Size of (object size information)
6. typeid (object type information)

S7. Ans.(d)
Sol. RAID-5 uses disk striping with distributed parity and allow reconstruction of data when disk fails.

S8. Ans.(b)
Sol. In SQL, the TRUNCATE TABLE Command quickly deletes all data and memory allocated in a table by deallocating the data pages used by the table. It is a Data Definition Language (DDL).

S9. Ans.(d)
Sol. A Programmable Logic Array (PLA) is used to implement combinational logic circuits. It has a set of programmable AND gates, which link to a set of programmable OR gates. Those can be conditionally complemented to produce an output.

S10. Ans. (a)

Quiz: Electrical Engineering 28 May 2020

 

Quiz: Electrical Engineering

Exam: UPPSC AE

Topic: Power electronics (electrical engineering)

 

Each question carries 1 mark.

Negative marking: 1/4 mark

Time: 10 Minute

 

Q1. A thyristor equivalent of thyratron tube is

(a) SCR

(b) UJT

(c) Diac

(d)Traic

 

 

Q2. An SCR is considered to be a semi-controlled device because

(a) it can be turned OFF but not ON with a gate pulse

(b) it conducts only during one half cycle of an alternating current wave.

(c) It can be turned ON but not OFF with a gate pulse.

(d) It can be turned ON only during one half cycle of an alternating voltage wave

 

 

Q3. In forward bias portion of the thyristor’s i-v characteristics, the number of stable operating region is

(a) One

(b)Two

(c) Three

(d) None

 

 

Q4. Turn-on of a thyristor takes place when

(a) anode to cathode voltage is positive

(b) anode to cathode voltage is negative

(c) there is a positive current pulse at the gate

(d) the anode to cathode voltage is positive and there is a positive current pulse at the gate

 

 

Q5. In the forward blocking region of a silicon-controlled rectifier, the SCR is

(a) In the off-state

(b) In the on-state

(c) reverse biased

(d) at the point of breakdown

 

 

Q6. Once an SCR is turned on, it remains so until the anode current goes below

(a) Triggering current

(b) Breakover current

(c) Threshold current

(d) Holding current

 

 

Q7. After firing an SCR, the gate pulse is removed. The current in the SCR will

(a) remain the same

(b) immediately fall to zero

(c) rise up

(d) rise a little and then fall to zero

 

 

Q8. When a thyristor is in ON state, its gate drive be

(a) removed to save power

(b) removed or may not be removed

(c) not removed as it will turn OFF the thyristor

(d) removed to avoid increased losses and higher junction temperature

 

 

Q9. In a thyristor the minimum current required to maintain the device in the ON state is called

(a) latching current

(b) ignition current

(c) holding current

(d) Avalanche current

 

 

Q10. In a thyristor the relation between the Holding current and latching current,

(a) more than latching current

(b) less than latching current

(c) equal to latching current

(d) equal to zero

 

Solutions

S1. Ans. (a)

Sol. SCR

 

S2. Ans. (c)

Sol. It can be turned ON but not OFF with a gate pulse.

 

S3. Ans. (b)

Sol. Two

 

S4. Ans. (d)

Sol. Turn-on of a thyristor takes place when the anode to cathode voltage is positive and there is a positive current pulse at the gate.

 

S5. Ans. (a)

Sol. In the forward blocking region of a silicon-controlled rectifier, the SCR is in the off-state.

 

S6. Ans. (d)

Sol. Once an SCR is turned on, it remains so until the anode current goes below Holding current.

 

S7. Ans. (a)

Sol. After firing an SCR, the gate pulse is removed. The current in the SCR will remain the same.

 

S8. Ans. (d)

Sol. removed to avoid increased losses and higher junction temperature

 

S9. Ans. (c)

Sol. Holding current

 

S10. Ans. (b)

Sol. less than latching current (IL)

 

 

Quiz: Electrical Engineering 27 May 2020

Quiz: Electrical Engineering
Exam: UPSSSC JE
Topic: Network theorems
Each question carries 1 mark.
Negative marking: 1/4 mark
Time: 10 Minute

Q1. Eight cells each of e.m.f. E and internal resistance r are connected in series. If due to oversight, two cells are connected wrongly, then equivalent e.m.f. and internal resistance of the combination are:
(a) 10 E and 6r
(b) 6 E and 10r
(c) E and 3r
(d) 4E and 8r

 

Q2. An ammeter has a resistance of 60 Ω and requires 10 mA for full-scale deflection. The shunt resistance S required to allow the meter to measure currents up to 100 mA is
(a) 5.56 Ω
(b) 2.5 Ω
(c) 6.67 Ω
(d) 8.75 Ω

 

Q3. Two resistors of resistances 6 Ω and 9 Ω are connected in parallel. The power dissipated in 6 Ω resistor is 15 W. The power dissipated is 9 Ω resistor is
(a) 10 W
(b) 24 W
(c) 6 W
(d) 16 W

 

Q4. Three capacitors of capacitance 12 μ F each are available. The minimum and maximum capacitances which may be obtained are
(a) 8 μ F, 24 μ F
(b) 4 μ F, 36 μ F
(c) 6 μ F, 33 μ F
(d) none of above

 

Q5. The desired voltage regulation for a single phase, 50 Hz transformer is zero. Its pu ohmic drop is 4% and pu reactive drop is 4%. The required power factor angle for the operation in degrees
a) 600
b) 900
c) 300
d) 450

 

Q6. For a separately excited dc machine of 25 kW, 250 V and armature resistance of 0.25 ohms, is running at 3000 rpm with supply of 255 V.
The electromagnetic power produced at the armature in kilo watts is
a) 0.5
b) 10
c) 5
d) 8

 

Q7. An alternator is to be used for generation purpose in an aircraft. The most suited operating frequency of the alternator should be
a) of 400 Hz to remove extra bulk
b) of 400 Hz to reduce losses
c) of 50 Hz to remove extra bulk
d) none of the mentioned

 

Q8. A 3-phase synchronous alternator is connected to the infinite bus is over excited, which corresponds to
a) inductor
b) capacitor
c) variable inductor
d) any of the mentioned

 

Q9. Separately excited dc generators are used in
a) Ward Leonard system of speed control
b) Hopkinson’s testing
c) Voltage control
d) None of the mentioned

 

Q10. Maximum torque in dc series motor is limited by
a) commutation
b) heating
c) field control
d) all of the mentioned

Solution

S1. (d)
Equivalent e.m.f. = E + E + E + E + E+ E – E – E=4E
Internal resistance = r+ r + r + r + r + r +r + r = 8r

S2. (c)
Full-scale voltage across meter = IR=10 mA×60 Ω=0.6 V. When circuit current is 100 mA, current through shunt = 100 – 10 = 90 mA.
∴ S=(0.6 V)/(90 mA)=6.67 Ω
S3. (a)
P=V^2/R or V=√(PR.) Since voltage is same in a parallel circuit, P_1 R_1=P_2 R_2 or 6×15 = P_2×9
∴P_2=10 W

S4. (b)
The capacitance is minimum when the three capacitors are connected in series and maximum when connected in parallel. i.e. 4 μ F and 36 μ F.

S5. (d)
Sol. The power factor angle is, tan (φ)=pu resistive drop/pu reactive drop
= 4/4= 1
tan^(-1)⁡1= 45°
S6. (c)
Sol. The current in armature, Ia = 255-250/0.25 = 20 A
Power = Eb*Ia = 250*20 = 5000 W
S7. (a)
Sol. The components to be used in aircrafts are made to operate at very high frequencies so that the size of the components to be used is reduced.
S8. (b)
Sol. In the mentioned condition the generator will correspondence as capacitor.
S9. (a)
Sol. Separately excited dc generators are used in Ward Leonard system of speed control.

S10. (a)
Sol. Commutation is the process which reduces the induced emf and so the torque.

Quiz Electronics Engineering 26 May 2020

Quiz Electronics Engineering
Exam: NIC
Topic: Miscellaneous
Date: 26/05/2020

Each Question carries 1 Mark
Negative Marking: 1/4
Time: 10 Minutes

Q1. A problem in mathematics is given to three students whose chances of solving it are respectively 1/2, 1/3 and 1/4. The probability that the problem will be solved is:
(a) 1/2
(b) 1/4
(c) 7/12
(d) 3/4

Q2. Which of the following applications include a phase-locked loop (PLL) circuit?
(a) Modems
(b) AM decoders
(c) Tracking filters
(d) All of these

Q3. The number of independent loops for a network with n nodes and b branch is
(a) n – 1
(b) b – n
(c) b – n + 1
(d) independent of the number of nodes

Q4. The number of station accommodated in a 100kHz bandwidth with highest modulating frequency of 5 kHz is
(a) 5
(b) 10
(c) 15
(c) 20

Q5. Compiler can diagnose
(a) grammatical errors only
(b) logical errors only
(c) grammatical as well as logical errors

Q6. The register which holds the address of the location to or from which data are to be transferred is called
(a) index register
(b) instruction register
(c) memory address register
(d) memory data register

Q7. In a binary max heap containing ‘n’ numbers, the smallest element can be found in time
(a) O(n)
(b) O(logn)
(c) O(log(logn))
(d) O(1)

Q8. The main difference between the operation of transmission lines and waveguides is that
(a) the latter are not distributed, like transmission lines
(b) the former can use stubs and quarter-wave transformers, unlike the latter
(c) transmission lines use the principal mode of propagation, and therefore do not suffer from low-frequency cut-off
(d) terms such as impedance matching and standing-wave ration cannot be applied to waveguides.

Q9. Which of the following circuit can be used as parallel to serial converter?
(a) Multiplexer
(b) Demultiplexer
(c) Decoder
(d) Digital Counter

Q10. To sort many large objects or structures, it would be most efficient to
(a) place reference to them in an array and sort the array
(b) place them in a linked list and sort the linked list
(c) place pointers to them in an array and sort the array
(d) place them in an array and sort the array

SOLUTIONS

S1. Ans.(d)
Sol. Given:
Probability of problem solved by first student is P(A) = 1/2
Probability of problem solved by second student is P(B) = 1/3
Probability of problem solved by third student is P(B) = 1/4

Finding probability of problem not solved in each case,
P’(A) = 1 – 1/2 = 1/2
P’(B) = 1 – 1/3 = 2/3
P’(C) = 1 – 1/4 = 3/4

Now, Probability of none of them solved the problem correctly is
P’(A) P’(B) P’(C) = 1/2 × 2/3 × 3/4 = 1/4

So, Probability of problem being solved is
⇒ P(A) P(B) P(C) = 1 – P’(A) P’(B) P’(C)
⇒ P(A) P(B) P(C) = 1 – 1/4 = 3/4

Therefore, The probability that the problem will be solved is 3/4 .

S2. Ans.(d)

S3. Ans.(c)
Sol.
No. of independent loop = b + n – 1
No. of Loop Equation = b – n + 1
No of independent of node = n – 1

S4. Ans.(b)
Sol. Given:
The highest modulating frequency = 5kHz
Bandwidth = 100 kHz

Let number of stations accommodated be ‘n’.

Now, n × 2 × 5 = 100
⇒ 10n = 100
So, n = 10

S5. Ans.(a)

S6. Ans.(c)
Sol. Memory Address Register (MAR) either stores the memory address from which data will be fetched from the CPU, or the address to which data will be sent for storage.

S7. Ans.(a)
Sol. The smallest element in a max heap is always present at a leaf node. As Heap is a complete binary tree and every complete binary tree contain up to n/2 nodes on leaf. So, to examine all of them we would need O(n) time.

S8. Ans.(c)

S9. Ans.(a)
Sol. Multiplexer has many inputs and one output so it is also called “Parallel to Serial Converter” or “Data Selector”.

S10. Ans.(b)
Sol. Linked list is most efficient because –
Insertion and Deletion is easy for rearranging of elements .
Memory is allocated at run-time.
consists of multiple data type.
proper utilization of memory.

Quiz: Electrical Engineering 25 May 2020

Quiz: Electrical Engineering

Exam: UPSSSC JE

Topic: Utilization of electrical energy

 

Each question carries 1 mark.

Negative marking: 1/4 mark

Time: 10 Minute

 

 

Q1. Air is dehumidified

(a) cooling

(b) chemical absorption

(c) heating

(d) both (a) and (b)

 

 

Q2. The conditions conductive to comfort depends upon

(a) humidity

(b) temperature

(c) air purity

(d) All of above

 

 

Q3. The speed of steam locomotive is controlled by

(a) applying breaks

(b) gear box

(c) regulating steam flow to engine

(d)  flywheel

 

 

Q4. The pulsating torque exerted by steam locomotive causes

(a) jolting and skidding

(b) hammer blow

(c) pitching

(d) all of the above

 

 

Q5. Steam engine drive

(a) has limited overload capacity

(b) is not clean drive

(c) is not suitable for urban or suburban service or for hauling heavy loads on steep gradients

(d) all of the above

 

 

Q6. Steam locomotive

(a) cannot be put into service at any moment

(b) cause considerable wear on the track

(c) need more repair and maintenance

(d) all of the above

 

 

Q7. Steam engine drive is not suitable for urban and suburban services as

(a) it is not clean drive

(b) coefficient of adhesion of steam locomotives is quite low

(c) steam locomotive cause considerable wear on the track

(d) steam locomotive has limited speed

 

 

Q8. Battery driven vehicles

(a) are easy to control and very convenient to use

(b) have low maintenance cost

(c) cause no pollution

(d) all of the above

 

 

Q9. Main traction systems used in India are those using

(a) steam engine locomotive

(b) diesel engine locomotive

(c) diesel electric locomotive

(d) All of the above

 

 

Q10. Battery operated trucks are used

(a) in power station

(b) for local delivery of goods in large town within maximum daily run up to 50-60 km

(c) in narrow gauge traction

(d) for main line service

 

 

Solutions

S1. Ans. (b)

Sol. Both cooling and chemical absorption are used to dehumidify.

S2. Ans. (d)

Sol. All factors are important.

S3. Ans. (c)

Sol. The speed of steam locomotive is controlled by regulating steam flow to engine.

S4. Ans. (a)

Sol. The pulsating torque exerted by steam locomotive causes jolting and skidding.

 

S5. Ans. (d)

Sol. All factors are true for steam engine

S6. Ans. (d)

Sol.  Feature of Steam locomotive

  • cannot be put into service at any moment
  • cause considerable wear on the track
  • need more repair and maintenance

 

S7. Ans. (b)

Sol. Steam engine drive is not suitable for urban and suburban services as coefficient of adhesion of steam locomotives is quite low .

 

S8. Ans. (d)

Sol. Benefits of Battery driven vehicles

  • are easy to control and very convenient to use
  • have low maintenance cost
  • cause no pollution

 

S9. Ans. (d)

Sol. All locomotives are used in main traction system.

S10. Ans. (b)

Sol. Battery operated trucks are suitable for local delivery of goods in large town within maximum daily run up to 50-60 km.

 

 

Quiz Electronics Engineering 25 May 2020

Quiz Electronics Engineering
Exam: NIC
Topic: Miscellaneous
Date: 25/05/2020

Each Question carries 1 Mark
Negative Marking: 1/4
Time: 10 Minutes

Q1. The number of address lines in the memory chip of size 8192 × 8 is –
(a) 8
(b) 12
(c) 13
(d) 16

Q2. Software that measures, monitors, analyzes and control real world events is called
(a) System Software
(b) Real-time software
(c) Scientific Software
(d) Business Software

Q3. Dividing a project into segments and smaller units in order to simplify analysis, design and programming efforts is called
(a) Modular approach
(b) Top down approach
(c) Bottom up approach
(d) Left-right approach

Q4. The Data Manipulation Language
(a) refers to data using physical addresses
(b) cannot interface with high-level programming language
(c) is used to define the physical characteristics of each record.
(d) none of these

Q5. A tuple in relational DBMS is equivalent to
(a) record
(b) field
(c) file
(d) database

Q6. Which one of the following set of gates are best suited for parity checking and parity generation?
(a) AND, OR, NOT
(b) EX-OR, EX-NOR
(c) NAND
(d) NOR

Q7. The library function exit() causes an exit from
(a) the loop in which it occurs
(b) the block in which it occurs
(c) the function in which it occurs

Q8. Can a DFA simulate NFA?
(a) No
(b) Yes
(c) Sometimes
(d) depends on NFA

Q9. Queue serves a major role in
(a) simulation of recursion
(b) simulation of arbitrary linked list
(c) simulation of limited resource allocation
(d) expressive evaluation

Q10. A complete graph with ‘n’ vertices is
(a) 2-chromatic
(b) (n/2) chromatic
(c) (n – 1) chromatic
(d) n chromatic

SOLUTIONS

S1. Ans.(c)
Sol. Each address consists of 8-bits. So, total addresses are 8192.
Let number of address lines be ‘n’.

Now, 2^n = 8192
2^n = 2^13
So, n = 13

Therefore, there are 13 address lines.

S2. Ans.(b)

S3. Ans.(a)

S4. Ans.(d)
Sol. DML consists of SQL commands to manipulate & process data stored into database objects. It is used to store, modify, retrieve, delete and update data in a database. Examples of DML commands include Select, Insert, Update and Delete commands.

S5. Ans.(a)
Sol. A tuple is simply a row contained in a table in the tablespace. A table usually consists of columns and rows in which row denotes records while column denotes attributes. A single row of a table that has a single record for such a relation is known as a tuple.

S6. Ans.(b)
Sol. With the help of EX-OR and EX-NOR gates we can check whether number of 1’s are even in number or odd in number but remaining other gates cannot tell. So these two gates are best suited for parity checking and parity generation.

S7. Ans.(d)
Sol. In the C Programming Language, exit() function terminates the program. File buffers are flushed, streams are closed, and temporary files are deleted.

S8. Ans.(b)

S9. Ans.(c)
Sol.
Simulation of recursion uses stack data structure.
Simulation of arbitrary linked lists uses linked lists.
Simulation of resource allocation uses queue so that first entered data can be given first priority during resource allocation.
Simulation of heap sort uses heap data structure.

S10. Ans.(d)
Sol. A complete graph with n vertices is n-chromatic, because all its vertices are adjacent.

Quiz: Electrical Engineering 21 May 2020

Quiz: Electrical Engineering
Exam: UPPSC AE
Topic: Analog and digital electronics (electrical engineering)

Each question carries 1 mark.
Negative marking: 1/4 mark
Time: 10 Minute

Q1. A FET transistor with an antiparallel body diode block:
(a) Bidirectional voltage and passes unidirectional current
(b) Bidirectional voltage and passes bidirectional current
(c) Unidirectional voltage and passes unidirectional current
(d) Unidirectional voltage and passes bidirectional current

 

Q2. Turn-on of a Thyristor takes place when
(a) anode to cathode voltage is positive
(b) anode to cathode voltage is negative
(c) there is a positive current pulse at the gate
(d) the anode to cathode voltage is positive and there is a positive current pulse at the gate

 

Q3. After firing an SCR, the gate pulse is removed. The current in the SCR will
(a) remain the same
(b) immediately fall to zero
(c) rise up
(d) rise a little and then fall to zero

 

Q4. When a thyristor is in ON state, its gate drive be
(a) removed to save power
(b) removed or may not be removed
(c) not removed as it will turn off the thyristor
(d) removed to avoid increased losses and higher junction temperature

 

Q5. Current in SCR to turn on transient can be reduced by
(a) connecting a small inductor in series with the anode
(b) connecting a small inductor in parallel with the anode
(c) connecting a small capacitor in series with the anode
(d) connecting a small capacitor in parallel with the anode

 

Q6. Which of following does not cause damage of an SCR?
(a) high current
(b) high rate of rise of current
(c) high temperature rise
(d) high rate of rise of voltage

 

Q7. When compared to those of a symmetrical thyristor, the turn off time and reverse blocking voltage of an asymmetrical thyristor are respectively
(a) large and large
(b) large and small
(c) small and large
(d)small and small

 

Q8. The duration of reverse recovery transient affects the following aspect in a power diode
(a) peak inverse voltage
(b) forward threshold voltage
(c) speed of response
(d) average current

 

Q9. Surge current rating of an SCR specifies the maximum
(a) repetitive current with rectangular wave
(b) non- repetitive current with sine wave
(c) non- repetitive current with rectangular wave
(d) repetitive current with sine wave

 

Q10. The dv/dt effect in SCR can result in
(a) Low capacitive charging current
(b) false triggering
(c) increased junction capacitance
(d) high rate of rise of anode voltage

 

Solutions
S1. Ans. (d)
Sol. Unidirectional voltage and passes bidirectional current

 

S2. Ans. (d)
Sol. the anode to cathode voltage is positive and there is a positive current pulse at the gate.

 

S3. Ans. (a)
Sol. remain the same

 

S4. Ans. (d)
Sol. removed to avoid increased losses and higher junction temperature

 

S5. Ans. (a)
Sol. connecting a small inductor in series with the anode

 

S6. Ans. (d)
Sol. high rate of rise of voltage

 

S7. Ans. (d)
Sol. Both quantities need to be small.

 

S8. Ans. (a)
Sol. The duration of reverse recovery transient affects the following aspect in a power diode peak inverse voltage.

 

S9. Ans. (b)
Sol. non- repetitive current with sine wave

 

S10. Ans. (b)
Sol. false triggering

Quiz Electronics Engineering 21 May 2020

Quiz Electronics Engineering
Exam: NIC
Topic: Miscellaneous
Date: 21/05/2020

Each Question carries 1 Mark
Negative Marking: 1/4
Time: 10 Minutes

Q1. In time division switches if each memory access takes 100 ns and one frame period is 125 µs, then the maximum number of lines that can be supported is
(a) 625 lines
(b) 1250 lines
(c) 2300 lines
(d) 318 lines

Q2. Which two are valid constructors for Thread?
1. Thread (Runnable r, String name)
2. Thread ()
3. Thread (int priority)
4. Thread (Runnable r, ThreadGroup g)
5. Thread (Runnable r, int priority)
(a) 1 and 3
(b) 2 and 4
(c) 1 and 2
(d) 2 and 5

Q3. Which of the following object types are generally autonomous, meaning that they can exhibit some behavior without being operated upon by another object.
(a) Passive
(b) Active
(c) Both (A) and (B)
(d) None of the above

Q4. The address of a class B Host is to be split into subnets with a 6 – bit subnet number. What is the maximum number of subnets and maximum number of hosts in each subnet?
(a) 8 subnets and 262142 hosts
(b) 6 subnets and 262142 hosts
(c) 62 subnets and 1022 hosts
(d) 8 subnets and 1024 hosts

Q5. Which level of RAID refers to disk mirroring with block striping?
(a) RAID level 1
(b) RAID level 2
(c) RAID level 0
(d) RAID level 3

Q6. Which of the following desired features are beyond the capability of relational algebra?
(a) Aggregate Computation
(b) Multiplication
(c) Finding transitive closure
(d) All of the above

Q7. A pipeline is having speed up factor as 10 and operating with efficiency of 80%. What will be the number of stages in the pipeline?
(a) 10
(b) 8
(c) 13
(d) None

Q8. In a ripple counter using edge-triggered JK flip-flops, the pulse input is applied to
(a) Clock input of all flip-flops
(b) J and K input of one flip-flop
(c) J and K input of all flip-flops
(d) Clock input of one flop-flop

Q9. Consider the following statements:
1. DC chopper can be used in both DC and AC drives.
2. For four-quadrant operation dual converter is required.
3. Output voltage from a chopper circuit depends both on load current and duty cycle.
4. In a step-down source, current can be discontinuous if duty cycle is LOW.
Which of the following statements are correct?
(a) 1,2 and 3
(b) 2 and 4
(c) 1,3 and 4
(d) 1 and 4

Q10. What is ‘Basis of Encapsulation’?
(a) object
(b) class
(c) method
(d) all of the mentioned

SOLUTIONS

S1. Ans.(a)
Sol. Given:
Each memory access time(T) = 100 ns
One frame period = 125 µs

We know that,
1 Frame Period = 2nT [where n is number of lines]

Now, 125 µs = 2n(100ns)
n = (125 × 10^(-6))/(200〖 × 10〗^(-9) )
So, n = 625

Therefore, the maximum number of lines that can be supported is 625.

S2. Ans.(c)
Sol. (1) and (2) are valid constructor for thread but (3), (4) and (5) are not legal constructor.

S3. Ans.(b)

S4. Ans.(c)
Sol. In class B network, first 2 octet are reserved for Network ID and remaining 2 for Host ID. So first 6 bits of 3rd octet are used for subnet and remaining 13 bits for hosts.
Maximum number of subnets = 2^6 – 2 = 64 – 2 = 62 subnets
2 is subtracted because subnet values containing all zero’s and all one’s are reserved for broadcast address so reducing the total number by 2.

Number of hosts = 2^10 – 2 = 1024 – 2 = 1022

Therefore, the maximum number of subnets and maximum number of hosts in each subnet are 62 subnets and 1022 hosts respectively.

S5. Ans.(a)
Sol. Characteristics of different RAID are:-
RAID-0: Disk array striping at the level of blocks rather than mirroring and parity, for data handling.
RAID-1: Disk mirroring with block stripping i.e., the replication of data to two or more disks. This is also called as RAID 10 or RAID 1+0.
RAID-2: stripes data at the bit level using a Hamming code to detect errors. Memory system have long parity bits for error detection and correction.
RAID-3: uses a parity disk to store the information instead of striping it with the data.

S6. Ans.(d)

S7. Ans.(c)
Sol. Given:
Speed up factor = 10
Efficiency = 80% = 0.8

We know that,
Efficiency = Speed up/No. of stages

Now, No. of stages = Speed up/Efficiency
No. of stages = 10/0.8
So, No. of stages = 12.5 = 13(approx.)

S8. Ans.(d)
Sol. A Ripple Counter is an asynchronous counter in which only the first flip-flop is applied with an external clock and all subsequent flip-flops are clocked by the output of the preceding flip-flop. Same is the case in edge-triggered JK flip-flop.

S9. Ans.(b)
Sol.
Statement 1 is Incorrect. DC choppers are used only for DC drives.
Statement 2 is Correct.
Statement 3 is Incorrect. Output voltage depends only on Duty cycle and independent of load current.
Statement 4 is Correct.

S10. Ans.(d)
Sol. Encapsulation refers to the bundling of data with the methods that operate on that data. It is used to hide the values or state of a structured data object inside a class, preventing unauthorized parties’ direct access to them. Also called combination of data-hiding and abstraction. Encapsulation provides contract to other object of what to hide and what to expose which can be accessed by other objects.

Quiz: Electrical Engineering 20 May 2020

Quiz: Electrical Engineering

Exam: UPSSSC JE

Topic: Switchgear and protection

 

Each question carries 1 mark.

Negative marking: 1/4 mark

Time: 10 Minute

 

Q1. The most serious consequence of a major uncleared short-circuit fault could be

(a) Blowing of fuse

(b) fire

(c) heavy voltage drop

(d) none of these

 

 

Q2. Which of the following result in a symmetrical fault?

(a) single phase to earth

(b) phase to phase

(c) All the three phases to earth

(d) two phase to earth

 

 

Q3. Which portion of transmission system is more prone to faults?

(a) Alternator

(b) transformer

(c) Overhead lines

(d) Underground cable

 

 

Q4. Which portion of power system is least prone to fault?

(a) Switchgear

(b) Alternator

(c) Overhead lines

(d) Transformer

 

 

Q5. The most common type of fault is

(a) Single phase to ground

(b)Two phase to ground

(c) Phase to phase

(d) three phase to ground

 

Q6. The per unit value of a 4 Ω resistance at 100 MVA base and 10 kV base voltage is

(a) 6 pu

(b)8 pu

(c)4 pu

(d)10 pu

 

 

Q7. Series reactor are used to

(a) improve the transmission efficiency

(b) improve the power factor of the power system

(c) improve the voltage regulation

(d) Bring down the fault level within the capacity of the switch gear

 

 

Q8. Current limiting reactors may be

(a) air cored air cooled

(b) oil immersed magnetically shielded

(c) oil immersed non magnetically shielded

(d) any of above

 

 

Q9. Symmetrical components are used in power system for the analysis of

(a) balanced 3 phased faults

(b) unbalanced 3 phase faults

(c) normal power system under steady condition

(d) Stability of system under disturbance

 

 

Q10. The positive sequence current of a transmission line is:

(a) always zero

(b) 1/3 of negative sequence current

(c) equal to negative sequence current

(d) 3 times negative sequence current

 

 

Solutions

 

 

 

S1. Ans.(b)

Sol. Fire is the most serious consequence.

 

S2. Ans.(c)

Sol. All the three phases to earth.

S3. Ans.(c)

Sol. Overhead lines

S4. Ans.(b)

Sol. Alternator

S5. Ans. (a)

Sol. The most common type of fault is Single phase to ground.

 

S6. Ans. (c)

Sol.  Rpu = R(ohm) ×MVA/(kV)^2
= 4 ×100/10^2 = 4 pu

S7. Ans. (d)

Sol. Bring down the fault level within the capacity of the switch gear.

S8. Ans. (d)

Sol. Any of above

S9. Ans.(b)

Sol. unbalanced 3 phase faults

S10. Ans. (b)

Sol. 1/3 of negative sequence current