RSMSSB JE Electrical Mock Test - 4 - Electrical Engineering (EE) MCQ

The correct answer is Ajayraj.Key Points

• The city was founded by Raja Ajayraj Chauhan in the 12th Century A.D.
• Ajmer is a popular pilgrimage center for Hindus as well as Muslims.
• It is a centre of culture and education.

Additional InformationArnoraj

• He constructed Anasagar Lake.
• He also constructed the Varah temple in Pushkar.
• He was defeated by the Chalukya ruler Kumarpal

Someshwar

• He belongs to the Chahmana dynasty.
• He issued Tomara styled copper coins.
• He also commissioned a temple dedicated to Vaidyanatha.

Ajayraj

• He was an Indian king who ruled the Sapadalaksha country.
• He defeated Sulhana (or Sollana), who was the commander of the Paramara king.
• He was a devotee of Lord Shiva.

The correct answer is 1, 3, and 4 only

Key Points

• Rajasthan is a dominant food grain crops state.
• It is considered a dry state of India. Thus it is highly dependent on the monsoon. Hence option 2 is incorrect
• Shifting agriculture is practiced mainly in the North-Eastern states of India.
• Walara is a type of shifting cultivation that is practiced in Rajasthan.
  • Districts of Banswara, Udaipur, and Dungarpur practice this type of agriculture.

Additional Information

• A significant proportion of the economy of Rajasthan is agrarian.
• The Agriculture sector accounts for nearly 22.5 %.
• The North-West Rajasthan is irrigated by Indira Gandhi Canal.
• Although Rajasthan is a big state, due to infertile land in the major portion, agriculture becomes difficult here.

• Hindustan Zinc is one of the world's largest and India's only integrated Zinc-Lead-Silver producers.
• The Company's smelters are located at Chanderiya, Dariba, and Debari in the State of Rajasthan.
• India's oldest Zinc smelter, located at Debari in the district of Udaipur, has a Zinc metal production capacity of 88,000 tonnes per annum.
• Dariba Smelting Complex, located in the district of Rajsamand, has a production capacity of 210,000 tonnes of Zinc and 100,000 tonnes of Lead per annum.
• Dariba Smelting Complex is uniquely self-sufficient with Zinc smelter, Lead smelter, and captive power plants of 160 MW, all located in the vicinity of Sindesar Khurd Mine and Rajpura Dariba Mine.

• Khetri is famous for a copper mine owned by Hindustan Copper Ltd.
• Neemrana is located in Alwar, close to Sariska national park.
• Nimbahera stone is a limestone that is found in the Chittorgarh district of Rajasthan.

Additional Information

• Rajasthan is a state in northern India.
• It covers 342,239 square kilometres or 10.4 per cent of India's total geographical area.
• It is the largest Indian state by area and the seventh-largest by population.
• Area: 342,239 km²
• Governor: Kalraj Mishra
• Capital: Jaipur
• Population: 6.89 crores
• Chief minister: Bhajan Lal Sharma

• Beed - Jhunjhunu
• Gogelav - Nagaur
• Jorbeed Gadhewal - Bikaner
• Gudha Vishnoi - Jodhpur
• Gogelav conservation reserve is situated in Nagaur of Rajasthan.
• It is situated in Nagaur, Rajasthan.
• It is spread over an area of 358 hectares.
• Chinkara deer are primarily found in this reserve.
• Apart from this, fox, mongoose, rabbit, patagoh, nilgai, wolf, partridge, peacock, and desert cat are found here.

• Guda Bishnoi Village is a tribal hamlet located at a distance of 15 km from Jodhpur city.
• The Khejri trees and the Guda Bishnoi Lake have peacocks, blackbucks, antelopes, chinkaras, cranes, and various migratory birds.
• Jorbeed situated some 12 km away from Bikaner in Rajasthan is one of the few places in India where vultures, which have almost vanished from the cities, can be sighted.
• Apart from vultures, different varieties of eagles can also be spotted in Jorbeed amongst other birds.
• The place is also a temporary home for yellow-eyed pigeons and a permanent home for chinkara and desert foxes.

• Rajasthan is a state in northern India.
• It covers 342,239 square kilometres or 10.4 per cent of India's total geographical area.
• It is the largest Indian state by area and the seventh-largest by population.
• Area: 342,239 km²
• Governor: Kalraj Mishra
• Capital: Jaipur
• Population: 6.89 crores
• Chief minister: Bhajan lal Sharma

The correct answer is All of the above.

Key Points

• Rajasthan State Industrial Development and Investment Corporation (RIICO):
  • RIICO is an apex organization engaged in promoting the growth of industrialization in the state.
  • RIICO's mission is to catalyze the planned and rapid industrialization of Rajasthan.
  • RIICO has set up 28 regional offices across Rajasthan to conduct the development and management of industrial areas.
  • RIICO has pioneered the industrialization of the state of Rajasthan by setting up industrial areas.
  • RIICO also acts as a financial institution by providing loans to large, medium, and small-scale projects.
• RIICO​'s Role:
  • Identifying investment opportunities.
  • Providing access to important information for setting up projects.
  • To assist in the translation of investment possibilities into concrete investment propositions.
  • The nodal agency for single-window clearance.
  • Ensuring prompt attention to proposals on behalf of investors along with all government departments/agencies.
  • Assisting in site selection and procurement of infrastructure facilities.
  • Intervention with government departments for necessary clearances.

The year 1896 was an El Nino year. During this period monsoon rainfall was considerably less than average. The next year(1897), the rains were sufficient but again in 1897-98, the rains were less, and the year 1899 was an El Niño year. This was the worst year because rainfall fell to 60-65%.

Important Points

Due to the two El Niño Years i.e. 1896 & 1899 in October 1897 Three Lakh square miles of the population of the Agra, Oudh, Bengal and the Central Provinces got affected.

• In November 1900, the Bombay Presidency, Central Provinces, Rajputana, etc. got caught in the grip of the famine.
• This was three and a half times the area affected previously.
• The famine claimed 90-100 Lakh lives, most severely affected were the Bombay Presidency as per the official figures and Rajputana as per the unofficial figures.
• Since the famine of 1899-1900 was in the Vikrami Samvat(historical Hindu calendar), it is known as Chhappania Akal or Chhappania Kal.

Thus, we can say that the great famine known as 'Chhapania-kal‘ among Rajasthani people occurred during 1899-1900 AD.

Additional Information

• Famine was followed by epidemic, malaria & cholera.
• The severity of the famine was so bad that the tribals of Rajputana, Madhya Pradesh (central Provinces), Gujarat (Bombay Presidency), Hissar and other places died in thousands.
• The tragedy is still sung in the folk songs of these areas.

The correct answer is the 12th century.

• Jaisalmer was established in the 12th century.

Additional Information

Jaisalmer State was a Bhati Rajput kingdom in the far-western part of present-day Rajasthan, India, from the mid-12th century CE until 1947.

• In 1156 CE, Rawal Jaisal moved his capital from Ludarva to Jaisalmer because the former was vulnerable to attacks from Turko-Afghan and Baloch tribes.
• The descendants of Jaisal continued to exercise absolute control over Jaisalmer until 1818 CE, when a treaty of subsidiary alliance with the British Empire made it a princely state, a British Protectorate still running its own internal affairs.
• Known as the Maharawal, the native ruler of the princely state was entitled to a 15-gun salute.
• The royal dynasty of Jaisalmer claims to be descended from the deified hero Krishna.
• The Bhati rulers originally ruled parts of Afghanistan; their ancestor Rawal Gaj is believed to have founded the city of Ghazni.
• According to James Tod, this city is present-day Ghazni in Afghanistan, while Cunningham identifies it as modern-day Rawalpindi.

The correct answer is 1-D, 2-B, 3-C, 4-A.

Key Points

The correct match of the civilizations with their excavator:

Additional Information

The correct answer is Teeja Manji Temple

Key Points

• Teja Manji Temple Located in Jodhpur, this temple was built by Pratap Kunwari, the queen of King Mansingh of Marwar.
• Maharaja Man Singh was the last independent Maharaja of the Marwar Kingdom and Jodhpur State.
• He was appointed as Heir Apparent by his grandfather Vijay Singh on 7 November 1791. However, upon Vijay Singh's death, Bhim Singh seized Jodhpur and proclaimed himself as the ruler of Marwar.

Additional Information

Kunj Bihari Temple

• Kunj Bihari Temple is an artistically and architectural beautiful temple in Jodhpur, Rajasthan. Its entrance and top are an example of marvellous architecture. There is a statue of Meera Bai, a great devotee of Lord Krishna at the entrance of the temple.
• The temple was built in 1847 by Gulab Rai, the Paswan (vice wife) of Maharaja Vijay Singh.

Mahamandir Temple

• Mahamandir Temple was built in 1812 CE and is well known for its marvellous piece of architecture that stands on 84 beautifully carved pillars. These pillars display intricate stone carvings that depict yoga postures. This temple is dedicated to Lord Shiva. The main pilgrimage site of the Nath sect.

Gangshaymaji Temple

• Gangshaymaji Temple was built by the erstwhile Maharaja of Jodhpur in the early 20th Century in Old city of Jodhpur.

The correct answer is Jaisalmer Fort.

Key Points

• Jaisalmer Fort
  • Jaisalmer Fort is famous for "Dhai Saka" (Two and a Half Sakas).
  • The first Saka of Jaisalmer Fort occurred during Alauddin Khilji's invasion (1296-1316 AD).
  • The second Saka occurred during Firoz Shah Tughlaq's invasion (1351-1388 AD), when Rawal Duda, Trilokasi, and other Bhati heroes were martyred in battle.
  • The third Saka is known as "Ardhasaka" ("Half Saka") because the warriors were martyred in battle, but no Jauhar (mass self-immolation) took place.
  • Rawal Lunakaran was martyred in 1550 AD in a battle with Amir Ali.
  • However, since the Bhatis emerged victorious, the women did not perform Jauhar.

Additional Information

• Gagron Fort
  • In 1423 AD, Sultan Hoshangshah of Mandu attacked Gagron Fort, and the ruler of that time, Achaldas Khinchi, was martyred.
  • The women performed Jauhar. This is known as the first Saka of Gagron.
  • In 1444 AD, Sultan Mahmud Khilji I of Malwa captured the fort.
  • At that time, the women of the fort performed Jauhar, which became known as the second Saka of Gagron.
• Ranthambore Fort
  • In 1301 AD, due to the betrayal of Hammir's ministers, Alauddin Khilji succeeded in capturing Ranthambore Fort.
  • During this time, Hammir's wife Rangdevi and daughter Deval De led the women in performing Jauhar, which is known as the first Saka of Ranthambore.
• Chittorgarh Fort
  • In the eighth century, Bappa Rawal, the founder of the Guhilot dynasty, seized the fort from the last Maurya ruler, Manamori.
  • First Saka - In 1303 AD, during the time of Alauddin Khilji, associated with the Jauhar of Padmini and the exceptional valor of Gora and Badal.
  • Second Saka - In 1534 AD, the Jauhar of Rani Karnavati, wife of Rana Sanga, during the time of Sultan Bahadur Shah of Gujarat.
  • Third Saka - In 1568 AD, the Jauhar of the wives of Jaimal and Fatta and the tales of their courageous sacrifice during the attack of Akbar.
  • These are known as the three Sakas of Chittorgarh.

The correct answer is a-4, b-2, c-3, d-1.

Key Points

Additional Information

• The Royal Rajasthan on Wheels is a luxury tourist train run by Indian Railways.
• It is modelled on the Palace on Wheels and follows a similar route through Rajasthan.
• Tourists are taken to several important tourists, wildlife, and heritage sites across Rajasthan.
• It is now known as Palace on wheels.
• The Royal Orient is an Indian luxury tourist train that runs between Gujarat and Rajasthan, covering important tourist locations in the two states.
  • Modelled on the Palace on Wheels, India's first luxury tourist train, the train offers tourists a taste of royal luxury while "showcasing the best of Indian culture and heritage".
• Village on Wheels refers to trains introduced by the Indian Railways to cater to budget tourists, especially villagers.
• The trains connect the selected tourist destinations, usually with a circular schedule.
• They are managed by the Indian Railway Catering and Tourism Corporation (IRCTC), a public-sector undertaking of the Railways.

The correct answer is (A) - (ii), (B) - (iv), (C) - (i), (D) - (iii)

Key Points

• Timber: Derived from the Teak tree (ii), known for its durability and water resistance, widely used in construction and furniture.
• Charcoal: Produced from Dhokda tree (iv), often used as a fuel source and in various industrial applications.
• Katha (Catechin): Extracted from the Khair tree (i), commonly used in making bidi (country cigarettes) and for its medicinal properties.
• Country Cigarettes: Made using leaves from the Tendu tree (iii), which are rolled to produce bidi, a traditional form of smoking in India.

Additional Information

• Timber is a significant forest produce used extensively in the construction and furniture industries.
• Charcoal is produced through the pyrolysis of organic material, primarily wood, and has applications in energy and industry.
• Katha is a valued product in Indian culture, used in traditional medicine and as a mouth freshener.
• Tendu leaves are vital for the bidi industry, which is a major source of income for many rural communities in India.
• Khair trees contribute to the ecosystem as they are nitrogen-fixing plants, enhancing soil fertility.

To control the speed of a 3-phase slip ring induction motor, the injected voltage in its rotor circuit must have the same frequency as the rotor voltage. This matching frequency allows for the adjustment of slip and enables speed control.

Concept:

Rotor emf injection method:
For below-rated speeds: In this method, injected emf has the same frequency of rotor slip frequency and that emf is 180° out of phase with rotor emf.

E2R is resultant emf in the rotor

E2R = E2 – E1

R2 is rotor resistance

T is the torque

s is the slip

Here, the value of rotor emf becomes less. To maintain constant torque, the value of slip will increase. Therefore, the speed will be decreased.

At this condition, effective rotor resistance increases.

For above-rated speeds: In this method, injected emf has the same frequency of rotor slip frequency and that emf is in phase with rotor emf.

E2R is resultant emf in the rotor

E2R = E2 + E1

R2 is rotor resistance
T is the torque
s is the slip

Here, the value of rotor emf becomes more. To maintain constant torque, the value of slip will decrease. Therefore, the speed will be increased.

Concept

A current always flows from a higher potential to a lower potential point. It is given by:

where, I = Current

V_H = Higher Potential

V_L = Lower Potential

R = Resistance

Calculation

Given, I = 36 mA

V_H = 12 V

V_L = 3 V

R = 250 Ω

Right-hand thumb rule

This law states that “If you imagine holding a current-carrying wire in your right hand with your thumb pointing towards the direction of electric current flow then the direction in which your fingers curl, gives the direction of lines of force of the magnetic field”.

Additional Information
1.) Fleming's Left Hand Rule

Fleming’s Left-hand rule states that if the thumb, forefinger, and middle finger of the left hand are stretched into mutually perpendicular directions such that the index finger and middle finger of a stretched left hand direct the magnetic field and electric current respectively then the thumb shows the direction of motion or force acting on the conductor.

2.) Fleming's Right Hand Rule

Fleming’s Right-hand rule states that if we arrange our thumb, forefinger, and middle finger of the right-hand perpendicular to each other, then the thumb points toward the direction of the motion of the conductor relative to the magnetic field, the forefinger points toward the direction of the magnetic field and the middle finger points towards the direction of the induced current.

Kelvin's double bridge

A kelvin double bridge is a modified version of the Wheatstone bridge, which is used to measure low resistance values in the range with high accuracy.

A Wheatstone bridge is used to measure resistance equal to or greater than 1ohm, but if we want to measure the resistance below 1ohm, it becomes difficult because the leads which are connected to the galvanometer add up the resistance of the device along with the resistance of leads leading to variation in the measurement of the actual value of resistance.

Hence in order to overcome this problem, we can use a modified bridge called the kelvin bridge.

In Kelvin's double bridge, the unknown resistance is given by:

X =

The applications of a unijunction transistor are:

• As a triggering device for SCR’s and Triacs
• Saw-toothed generators
• Simple oscillators
• Phase control
• Timing circuits

The simplest and most common application of all UJT circuits is the Relaxation Oscillator producing non-sinusoidal waveforms.

The inverse transducer is defined as a device that converts an electrical quantity into a non-electrical quantity.

A piezoelectric crystal acts as an inverse transducer because when a voltage is applied across its surfaces, it changes its dimensions causing a mechanical displacement.

Note:

A piezoelectric sensor is a device that uses the piezoelectric effect to measure changes in pressure, acceleration, temperature, strain, or force by converting them to an electrical charge. It is used to measure displacement.

The correct answer is option 4): β - α

Concept:

The circuit and waveform for a single-phase full controlled bridge converter supplying an R-L load with continuous load current are shown below.

For the above waveform average voltage is given by Average voltage,

In a single-phase full converter, for discontinuous load current and extinction angle β > π, each SCR conducts for β - α if the firing angle is α.

Concept:

Real Power transmitted to the load can be given as,

P = Vrms × Irms × cos ϕ

Where,

Vrms = load terminal voltage in volt

Irms = load current in amper

cos ϕ is the power factor of the load

ϕ is the power factor angle

Calculation:

v = 100√2 sin (500t) V

I = 10√2 sin (500t + π/3) A

Power factor angle

Active power consumed by load = V_rms× I_rms × cos ϕ

=

= 500 W

Concept:

The quality factor is defined as the ratio of the maximum energy stored to maximum energy dissipated in a cycle

The quality factor in a series RLC circuit is given by:

Calculation:

If R, L, and C double from its original value, the quality factor becomes half of the previous value.

New quality factor (Q) will be:
Q = 100/2 = 50

Concept:

• The firm power of a power system is the reliable and constant power output that can be consistently delivered by the system.
• It is determined by considering the availability factors of the different power sources in the system.

Calculation:
The firm power is calculated by summing up the product of the installed capacity and the availability factor for each power source. In this case:
Coal-fired power plant: 800 MW * 0.8 = 640 MW
Wind farm: 400 MW * 0.5 = 200 MW
Now, summing up these values:
Firm power = 640 MW (coal) + 200 MW (wind) = 840 MW
Therefore, the correct answer is: 840 MW

Concept:
If load Resistance is varying then it is known as load Regulation.

Under load Regulation:

IL max = IS – IZ min
IL min = IS – IZ max

Calculation:

VZ = 6 V

IZ min = 5 mA

Since we want a constant 6 V across R

IL Max = IS – IZ min = 80 – 5

= 75 mA
I_L = 6/R

Concept:

We know that for second-order system damping ratio

K = gain constant

A chopper is a static device which is used to obtain a variable dc voltage from a constant dc voltage source. Also known as a dc-to-dc converter.

They can step up the DC voltage or step down the DC voltage levels.

Types of Choppers:

• Type A Chopper or First-Quadrant Chopper
• Type B Chopper or Second-Quadrant Chopper
• Type C Chopper or Two-quadrant type-A Chopper
• Type D Chopper or Two-quadrant type-B Chopper
• Type E Chopper or fourth-quadrant Chopper

Note:

Power electronic circuits can be classified as follows.

1. Diode rectifiers:

• A diode rectifier circuit converts AC input voltage into a fixed DC voltage.
• The input voltage may be single phase or three phase.
• They find use in electric traction, battery charging, electroplating, electrochemical processing, power supplies, welding and UPS systems.

2. AC to DC converters (Phase controlled rectifiers):

• These convert AC voltage to variable DC output voltage.
• They may be fed from single phase or three phase.
• These are used in dc drives, metallurgical and chemical industries, excitation systems for synchronous machines.

3. DC to DC converters (DC Choppers):

• A dc chopper converts DC input voltage to a controllable DC output voltage.
• For lower power circuits, thyristors are replaced by power transistors.
• Choppers find wide applications in dc drives, subway cars, trolley trucks, battery driven vehicles, etc.

4. DC to AC converters (Inverters):

• An inverter converts fixed DC voltage to a variable AC voltage. The output may be a variable voltage and variable frequency.
• In inverter circuits, we would like the inverter output to be sinusoidal with magnitude and frequency controllable. In order to produce a sinusoidal output voltage waveform at a desired frequency, a sinusoidal control signal at the desired frequency is compared with a triangular waveform.
• These find wide use in induction motor and synchronous motor drives, induction heating, UPS, HVDC transmission etc.

5. AC to AC converters: These convert fixed AC input voltage into variable AC output voltage. These are two types as given below.

i. AC voltage controllers:

• These converter circuits convert fixed AC voltage directly to a variable AC voltage at the same frequency.
• These are widely used for lighting control, speed control of fans, pumps, etc.

ii. Cycloconverters:

• These circuits convert input power at one frequency to output power at a different frequency through a one stage conversion.
• These are primarily used for slow speed large ac drives like rotary kiln etc.

6. Static switches:

• The power semiconductor devices can operate as static switches or contactors.
• Depending upon the input supply, the static switches are called ac static switches or dc static switches.

Overload protection:

• Overload protection is protection against a running overcurrent that would cause overheating of the protected equipment.
• Overload protection typically operates on an inverse time curve where the tripping time becomes less as the current increases.
• The chances of overloading faults on alternators are negligible. The actual power generation depends on prime mover which is continuously observed and regulated by governors and regulators.
• Furthermore, such protection on the alternator will take out the alternator for a long time even in case of harmless momentary troubles. Thus leading to blackouts and interruption of electric supply.
• Hence, except alternators, they are used for all devices including motors, transformers, and busbars, etc.

Permanent Magnets:

Permanent magnets are magnets with magnetic fields that do not dissipate under normal circumstances. They are made from hard ferromagnetic materials, which are resistant to becoming demagnetized.

Permanent magnets are made from a material that will inherit the properties of a strong magnetic field when exposed to it.

Properties:

Residual induction:

The residual induction is any magnetic induction that remains in a magnetic material after removal of an applied saturating magnetic field, measured in gauss or tesla. Residual induction is also known as magnetic remanence.

Coercivity:

• Coercivity (or the coercive field) is the property of a material to resist demagnetization due to the intensity of the material's magnetic field
• Coercivity is measured by the extent to which a demagnetizing field must be applied to reduce the material's magnetism to zero
• Permanent magnets are composed of materials with a high coercivity which retains their inherited magnetic fields under most conditions, unless intentionally demagnetized

Hysteresis loop:

• Wider hysteresis loops have high retentivity, coercivity, and saturation due to their larger hysteresis loop area
• These loops are typically found in hard magnetic materials
• Due to the size, these hysteresis loops have low initial permeability which leads to higher energy dissipation
• For these reasons, they are utilized in permanent magnets that have high resistance to demagnetization
• Demagnetization is more difficult to achieve in these wider hysteresis loops because there is a larger area to cover when reversing the hysteresis loop direction back to its original paramagnetic state.

In large alternators, damper windings are used to

• Reduce the vibrations (hunting)
• To increase the stability i.e. the voltage fluctuations will get reduced

The damper winding in a synchronous motor performs two functions:

• Prevents hunting (damped out oscillations)
• Provides starting torque (made self-starting)

Note: Under normal running conditions, damper winding does not carry any current.

Important Points

Hunting is a phenomenon that occurs in synchronous motors due to varying load or supply frequency.

Causes of hunting

• Periodic variation of load
• Sudden changes in load
• Faults occur in the system when supplied by the generator
• Sudden change in the field current
• Cyclic variations of the load torque

Effects of hunting

• It can lead to loss of synchronism
• It can cause variations of the supply voltage producing undesirable lamp flicker
• The possibility of resonance condition increases. If the frequency of the torque component becomes equal to that of the transient oscillations of the synchronous machine, resonance may take place
• Large mechanical stresses may develop in the rotor shaft
• The machine losses increases and the temperature of the machine rises

Kirchoff's Current Law (KCL):

According to the KCL: at any node, the sum of all incoming currents is always equal to the sum of all outgoing currents.

I₁ + I₄ = I₂ + I₃ + I₅

Calculation

Consider voltage at point 'a' is V and also take incoming current as negative.

Applying KCL at node A:

V = 1.5 volts

Additional Information

Kirchoff's Voltage Law (KVL):

According to Kirchhoff's Voltage Law, The voltage around a loop equals the sum of every voltage drop in the same loop for any closed network and equals zero.
V = VR₁ + VR₂ + VR₃
V = I(R₁ + R₂ + R₃)

Concept:

• The characteristic equation for a given open-loop transfer function
• G(s) is 1 + G(s) H(s) = 0
• According to the Routh tabulation method, The system is said to be stable if there are no sign changes in the first column of the Routh array The number of poles lies on the right half of s plane = number of sign changes

Calculation:

Characteristic equation: s³ + 3s² + 2s + k = 0 By applying the Routh tabulation method,

For the system to become stable, the sign changes in the first column of the Routh table must be zero.

6 - K > 0 and K > 0,

The range of k for stable operation 0 < K < 6