MPPGCL JE Electronics Mock Test - 3 Free Online Test 2026

Controlling can be defined as that function of management that helps to seek planned results from the subordinates, managers, and at all levels of an organization. The controlling function helps in measuring the progress towards the organizational goals & brings any deviations, & indicates corrective action.

Key Points

Limitations of Controlling:

1. Difficulty in setting quantitative standards:

• Control system loses its effectiveness when the standard of performance cannot be defined in quantitative terms and it is very difficult to set the quantitative standard for human behavior, efficiency level, job satisfaction, employee’s morale, etc.
• In such cases, judgment depends upon the discretion of the manager.

2. No control on external factors:

• An enterprise cannot control external factors due to its variation and causes such as government policy, technological changes, change in fashion, change in competitor’s policy, etc.

3. Resistance from employees:

• Employees often resist control and as result effectiveness of control reduces.
• Employees feel control reduces or curtails their freedom.
• Employees may resist and go against the use of cameras, to observe them minutely.

4. Costly affair:

• Control is an expensive process it involves a lot of time and effort as sufficient attention has to be paid to observe the performance of the employees.
• To install an expensive control system organizations have to spend a large amount.
• Management must compare the benefits of controlling systems with the cost involved in installing them.
• The benefits must be more than the cost involved then only controlling will be effective otherwise it will lead to inefficiency.

Therefore, option 4 is the correct answer.

• The radar altimeter measures absolute altitude, i.e. the altitude that the aircraft is above the ground (Above ground level)
• The radar altimeter system sends out a radio wave, and that radio wave bounces off the ground and is received.
• AGL is computed by taking the speed of the radio wave and the amount of time for it to return.
• Unlike radar, the signal is not pulsed, but is Frequency modulated and is transmitted at 4300 MHz at 350 milliwatts.
• Radar Altimeters operate between - 20 and 2500 feet.

Concept:

The average value of a periodic waveform is given as

It is also calculated by calculating the area of the given waveform.

Where A is the area

Calculation:

The given figure consists of rectangular pulses.

Area of rectangle = L × B

Where L = Length

B = Breadth

Concept:

The reflection coefficient gives the percentage of incident voltage reflected from the load.

Mathematically, this is defined as:

Γ = Reflection coefficient

Z_L = Load Impedance

Z_o = Characteristic Impedance.

Application:

Given Z₀ = 100 Ω and Z_L = 200 Ω

Voltage reflection coefficient will be:

A frame check sequence (FCS) refers to an error-detecting code added to a frame in a communications protocol

Layer 2 Frame Format:

Ethernet Frame Format consists of Cyclic Redundancy Check (CRC) in Frame check sequence Field.

CRC size → 4 bytes

1 byte = 8 bit

∴ 4 byte = 4 × 8 bits = 32 bits

Hay’s bridge is used for measurement of inductance of coils with high quality factor.

Concept:

We know that

P = I²R

Where 

P = Power 

I = Current

R = Resistance

In this, the current through the bulbs is fixed.

The resistance of the bulb is inversely proportional to the wattage of the bulb.

Calculation:

Given

R₆₀ < R₄₀

The resistance of 40 W is more than 60 W bulbs.

Hence R₆₀ Consumes less power and is less bright

So, the 40 bulb glows brighter.

Concept:

The voltage standing wave ratio is defined as the ratio of the maximum voltage (or current) to the minimum voltage (or current).

VSWR is also given by:

Γ = Reflection coefficient, defined as:

Z_L = Load impedance

Z₀ = Characteristic Impedance

For Γ_L varying from 0 to 1, VSWR varies from 1 to ∞.

Application:

Given Z_L = Z₀

The reflection coefficient is calculated to be:

VSWR for Γ = 0 equals 1, which is the minimum value (because it varies from 1 to ∞)

Class C amplifier:

• Class C power amplifier is a type of amplifier where the active element (transistor) conduct for less than one-half cycle of the input signal.
• Less than one-half cycle means the conduction angle is less than 180° and its typical value is 80° to 120°.
• The reduced conduction angle improves the efficiency to a great extends but causes a lot of distortion.
• The theoretical maximum efficiency of a Class C amplifier is around 90%.
• In a Class C Amplifier efficiency and distortion, both are maximum.

Important Point

PUSH RP (Pre-decrement):

This instruction copies the contents of RP to stack.

For every PUSH:

• Decrement SP and PUSH RP_H
• Decrement SP and PUSH RP_L

POP RP (Pre-increment):

Used for retrieving the elements stored in the stack.

For every POP:

• Get 1 byte from stack to RP_L and increment.
• Get 1 byte from stack to RP_H and increment.

Let stack pointer (SP) = FFFF H and DE = 3025H ; HL = B315H

(a) PUSH H and

(b) PUSH D are as shown:

PUSH D: contents of DE register is copied to (FFFC and FFFB) H

PUSH H: contents of HL = B315 register, is copied to (FFFE & FFFD)H

Similarly,

c) POP J and

d) POP D are as shown:

POP H retrieves the contents to HL register

POP D: retrieves the contents to the DE register.

∴ After the execution of instructions, the contents of the DE register pair is DE = B315 H, which is

equal to HL before execution.

∴ [H] → [D]

[L] → [E]

• PSK: It stands for phase shift keying.
• In PSK, binary 1 is represented with the actual carrier, and 0 is represented with the 180^o phase shift of carrier.
• 1 is represented as  s(t) = Accos(2πf_ct)
• 0 is represented as  s(t) = - Accos(2πf_ct)
• As in PSK, one bit is transmitted in a specific time constant.
• Similarly, in 16 PSK, log₂(16) = 4 bits are transmitted in a specific time constant which is known as 16-ary PSK.

B.W. of PSK = 2R_b

Whereas for M-ary PSK,

Hence M-ary is preferred due to less bandwidth.

• In 16 APSK, Amplitude and Phase both vary in a pattern as shown in the figure.
• 16 QAM is a signal in which two carriers shifted in phase by 90 degrees are modulated and combined. As a result of their 90° phase difference, they are in quadrature.
• Often one signal is called the In-phase or “I” signal, and the other is the quadrature or “Q” signal.

Hence the given figure is 16 QAM.

So the solution is option (2).

Concept:

Any given circuit will be at the resonant frequency when the net impedance is purely resistive.

Calculation:

Calculating the net-admittance of the given combination because the impedances are in parallel.

Y_net = Y₁ + Y₂

Replacing s with jω, we get;

At resonance, the imaginary part is zero and Y_net will be only real.

Given, R = 1Ω

L = 2μH

C = 1μF.

1 + ω₀² (4μ²) = 2

ω₀² × 4μ² = 1

ω₀ = 1/2μ = 0.5 M_­rad/sec

Now,  at resonance:

Y_net = ½

R_net = 2Ω

There are three generations in cellular telephony.

• First Generation: It was designed for voice communication using analog signals. Example: AMPS (Advanced mobile phone system) is one of the leading analog cellular system. It uses FDMA to separate channels in a link. AMPS operates in the ISM 800 MHz band.
• Second Generation: To provide higher quality mobile voice communication, these generation of cellular phone are required. These are used for digital voice communication. Example: D- AMPS, CDMA, GSM. The product of evolution of analog AMPS into a digital system is digital AMPS. D-AMPS uses TDMA and FDMA. GSM stands for global system for mobile communication. It provides duplex communication by using two digital bands.
• Third generation: It refers to a combination of technologies that provide a variety of services. It can provide both digital data and voice communication. Main goal of third generation cellular telephony is to provide universal personal communication. These are based on broadband CDMA. Example: IMT-DS, IMT-MC etc

Norton's Theorem :

Any linear bilateral network consisting of multiple resistances and sources can be replaced by a resistor R_N in parallel of Current source I_N .

Calculation:

R_N : 

Disable all independent sources and find equivalent resistance.

R_N = ( 20 || 10 ) + 20 = 26.6 ohm

I_N :

Short circuited current

Let node voltage of 10 ohm is V

Apply nodal analysis

V = 2.5V

I_N = V /20 = 125 mA

Sampled data system:

When the signal or information at any or some points in a system is in the form of discrete pulses, then the system is called discrete data system or sampled data system.

The following methods suitable for the stability analysis of sampled data control systems.

• Jury’s stability test
• Root locus technique
• Bilinear transformation

Merits:

• Systems are highly accurate, fast and flexible
• Use of time sharing concept of digital computer results in economical cost and space.
• Digital transducers used in the system have better resolution.
• The digital components are less affected by noise, non-linearities and transmission errors of noisy channel.

Demerits:

• Conversion of analog signals to discrete-time signals and reconstruction introduce noise and errors in the signal.
• Additional filters have to be introduced in the system if the components of the system does not have adequate filtering characteristics.

Concept:

 A decoder is a combinational circuit that converts n lines of input into 2n lines of output.

Decoder expansion

Number of D₂ decoder required is given as:

∑ K = K₁ + K₂ + K₃ + ------ 

Calculation:

Given decoder 1 is 3 × 8 and the second decoder is 4 × 16

Number of 3 × 8 decoders = 2 + 0

Number of 3 × 8 decoders = 2

The implementation is shown below.

Important Point

The Correct Answer is Option (1) i.e A program.

• An operating system is a software or a program that manages computer hardware, software resources, and provides common services for computer programs.
• An operating system is an interface between the computer user and computer hardware.
• The dominant desktop operating system is Microsoft Windows with a market of around 82.74%, followed by macOS by Apple Inc.
• Some popular operating system include Linux operating system, Windows operating system, VMS, OS/400, macOS, etc.
• Some of the important functions of an operating system are :
  • Memory Management
  • Processor Management
  • Device Management
  • File Management
  • Security
  • Job Accounting
  • Co-ordination between other software and users.

HTTP: Multiple TCP connections can be used at client and server end.

FTP: For FTP also multiple connections can be used at the same time.

TELENT: Only one TCP connection is allowed at a time.

SMTP: SMTP also allows only one TCP connection at a time.

Concept:

In a semiconductor, the probability of finding an electron at an energy level E is given by:

E_F = fermi level

Calculation:

Given, E_F = E_C

The probability of finding electrons in the energy level E = E_C + KT will be:

f(E_C + KT) = 0.268

Moving Iron Instruments are the most common type of ammeter and voltmeter used at power frequencies in laboratories.

These instruments are very accurate, cheap, and rugged as compared to other AC instruments.

Working Principle of Moving Iron Instruments:

In Moving Iron Instruments, a plate or van of soft iron or of high permeability steel forms the moving element of the system.

The iron van is so situated that it can move in the magnetic field produced by a stationary coil.

The below figure shows a simple moving iron instrument.

The stationary coil is excited by the current or voltage under measurement.

When the coil is excited, it becomes an electromagnet, and the iron van moves in direction of offering a low reluctance path.

Thus the force of attraction is always produced in a direction to increase the inductance of the coil.

Mind that as the van follows the low reluctance path, the net flux in the air gap will increase which means increased flux linkage of the coil, and hence inductance of coil will increase.

It shall also be noticed that the inductance of the coil is variable and depends on the position of the iron van.

Torque Equation of Moving Iron Instruments:

Deflecting torque in Moving iron Instruments is given as

Td =  (1/2)I²(dL/dƟ)

In moving iron instruments, the controlling torque is provided by spring. Controlling torque due to spring is given as

Tc = KƟ

Where K = Spring constant

Ɵ = Deflection in the needle

In equilibrium state, deflecting and controlling torque shall be equal as below.

Deflecting Torque = Controlling Torque

⇒ Td = Tc

⇒ (1/2)I²(dL/dƟ) = KƟ

⇒ Ɵ = (1/2)(I²/K)(dL/dƟ)

Let the numerator = x and denominator = y

y + 3 = 2y ⇒ y = 3

x +1= 3 ⇒ x = 2

∴ xy = 2 × 3 = 6

Hence, option A is correct.

Following the common explanation, we get “C and Z sits two places away from Y”.
Hence, option D is correct.
Final Arrangement:

Common Explanation:
References:
1. Two people are sitting between A and Z.
2. C sits fourth to the right of Z.
3. The number of people sitting to the right of A is the same as the number of people sitting to the left of Z.
4. The number of people sitting between A and C is the same as the number of people sitting between X and C.
5. X is an immediate neighbour of D, who sits on one of the ends.
6. The number of people sitting between D and C is the same as the number of people sitting between C and Y.
7. At most 25 people are sitting in a row.
Inferences:
From reference 1, we get two possible cases.
From reference 7, case2 was eliminated.
Hence, Case 1 is the final arrangement.

Booth capturing is a type of electoral fraud in which party loyalists "capture" a polling booth and vote in place of legitimate voters to ensure that their candidate wins.

Checking Statement I:

Using the above references, we get the following arrangement:

Clearly, D was born in July.

Hence data in statement I is sufficient to answer the question.

Checking Statement II:

Using the above references, we get the following arrangement:

Clearly, D was born in July.

Hence data in statement II is sufficient to answer the question.

Here, the data in either Statement I or II alone is sufficient to answer the question.

Hence, Option C is correct.

As the cry of 'Dog' is called 'Bark' in the same way the cry of 'Goat' is called 'Bleat'.

Product of two numbers = HCF × LCM
1280 = 8 × LCM
160 = LCM