JKSSB Foreman 2025 Solved Question Paper

Question 1

A scientist proposes that the speed V of a wave traveling along a stretched string depends on the tension in the string T and the linear mass density of the string $\mu$. Using dimensional analysis, derive the possible relation between V, T, and $\mu$:

Accepted Answer

Option B: V = T^(1/2) * u^(-1/2). Using dimensional analysis: Speed $[V] = [LT^{-1}]$, Tension $[T] = [MLT^{-2}]$, Linear density $[\mu] = [ML^{-1}]$. Let $V \propto T^a \mu^b \implies [LT^{-1}] = [MLT^{-2}]^a [ML^{-1}]^b = M^{a+b} L^{a-b} T^{-2a}$. Equating powers: $a + b = 0$, $-2a = -1 \implies a = 1/2, b = -1/2$. Thus, $V = T^{1/2} \mu^{-1/2} = \sqrt{rac{T}{\mu}}$. Choice B.

Question 2

What is the effect of increasing the banking angle of a road?

Accepted Answer

Option A: The vehicle can turn at a higher speed safely. Banking of roads provides the necessary centripetal force ($N\sin	heta$) from the horizontal component of the normal reaction, allowing vehicles to negotiate sharp curves at higher speeds safely without relying on tire friction ($v = \sqrt{rg	an	heta}$).

Question 3

Match the following modes of heat transfer with their examples:
Modes of Heat Transfer:
i. Conduction
ii. Convection
iii. Radiation

Examples:
1. Boiling water in a pot
2. Metal spoon handle heating up in hot soup
3. Feeling the warmth of the Sun

Choose the correct statement:

Accepted Answer

Option D: i-2, ii-1, iii-3. i -> 2 (Conduction: direct molecular thermal vibration through metal spoon), ii -> 1 (Convection: bulk fluid circulation currents in boiling water), iii -> 3 (Radiation: electromagnetic thermal infrared rays from Sun). Correct match: i-2, ii-1, iii-3.

Question 4

Which of the following statements about total internal reflection is/are correct?
1. It occurs when light travels from a denser medium to a rarer medium at an angle greater than the critical angle.
2. The critical angle is the angle of incidence at which the refracted ray emerges along the boundary of the two media.
3. It is responsible for the shining of a crack present in a vessel made out of glass.
Choose the correct statement:

Accepted Answer

Option D: 1, 2 and 3. All three statements are correct: TIR occurs when $i > 	heta_c$ travelling denser-to-rarer (1), Critical angle is the incidence angle where angle of refraction $r = 90^\circ$ along the boundary (2), and glass cracks shine due to TIR at the glass-air trapped interface (3). Correct: 1, 2 and 3.

Question 5

Which of the following is NOT a primary reason for the decrease in resistance of a semiconductor with an increase in temperature?

Accepted Answer

Option C: Increase in the mobility of charge carriers. In semiconductors, increasing temperature excites covalent bond electrons across the band gap to the conduction band, exponentially increasing carrier density ($n$). Carrier mobility ($\mu$) actually DECREASES at higher temperatures due to increased thermal lattice acoustic phonon scattering; thus, 'Increase in mobility' is NOT a reason.

Question 6

How does the cross-sectional area of solenoids affect the coupling coefficient (K)?

Accepted Answer

Option C: Increasing the cross-sectional area increases the coupling coefficient.. Magnetic coupling coefficient $K = rac{M}{\sqrt{L_1 L_2}}$. Increasing the cross-sectional area of the mutual core maximizes common magnetic flux linkage ($\Phi = B \cdot A$) between primary and secondary windings, thereby increasing the coupling coefficient ($K ightarrow 1$).

Question 7

Which of the following statements about a PN junction diode is incorrect?

Accepted Answer

Option D: The depletion region increases in forward bias. Statement D is incorrect: In Forward Bias (anode positive, cathode negative), the applied external electric field opposes the built-in potential barrier, which Narrows and Decreases the Depletion Region (the depletion layer widens only in reverse bias).

Question 8

Which of the following is NOT a favorable condition for forming an ionic bond?

Accepted Answer

Option D: Similar electronegativity between the two bonding atoms.. Formation of an Ionic Bond requires a Large Electronegativity Difference ($\Delta EN > 1.7$) between electropositive metal and electronegative non-metal. 'Similar electronegativity' promotes non-polar covalent bonding, NOT ionic bonding.

Question 9

Which of the following statements about the factors affecting bond length is/are correct?
1. The Bond length increases with the size of the atom ($HI > HBr > HCl > HF$).
2. An increase in bond order increases the bond length.
3. The greater 's' character (proportion of the s orbital in a hybrid orbital) shortens bond length.
Choose the correct statement:

Accepted Answer

Option B: 1 and 3. Statements 1 and 3 are correct: Bond length increases as atomic radius increases ($HI > HBr > HCl > HF$ - 1), and higher s-character brings shared electrons closer to the nucleus, shortening bond length ($sp < sp^2 < sp^3$ - 3). Statement 2 is false because increasing bond order shortens bond length (triple < double < single). Correct: 1 and 3.

Question 10

Match the different processes used to remove the hardness of water with the main element/chemical in that process:
Name of Process:
i. Calgon's Process
ii. Gan's Permutit Method
iii. Ion Exchange Resin Method
iv. Clarks Method

Main Element/Chemical:
1. Calcium hydroxide
2. Anion exchange resin (RNH2OH)
3. Sodium-hexa-meta-phosphate $(NaPO_3)_6$
4. Sodium aluminum ortho silicate

Choose the Correct Option:

Accepted Answer

Option C: i-3, ii-4, iii-2, iv-1. i -> 3 (Calgon's process: Sodium hexametaphosphate $Na_2[Na_4(PO_3)_6]$), ii -> 4 (Permutit process: hydrated sodium aluminum silicate zeolite $Na_2O \cdot Al_2O_3 \cdot xSiO_2 \cdot yH_2O$), iii -> 2 (Ion Exchange: synthetic cation/anion exchange resins), iv -> 1 (Clark's lime process: addition of calculated slaked lime $Ca(OH)_2$). Correct match: i-3, ii-4, iii-2, iv-1.

Question 11

Which of the following statements is NOT correct regarding the importance of pH in everyday life?

Accepted Answer

Option C: The pH range of all the fruits is greater than 7.. Statement C is NOT correct: Natural edible fruits contain organic acids (citric acid, malic acid, tartaric acid, ascorbic acid) and have an acidic pH strictly Less Than 7 ($pH pprox 2.5	ext{ to }4.5$).

Question 12

Which of these alloys is lightweight and commonly used in aircraft manufacturing?

Accepted Answer

Option B: Duralumin. Duralumin (an alloy of 94% Aluminum, 4% Copper, 1% Magnesium, and 0.5% Manganese) combines exceptional tensile strength with lightweight low density, making it the premier structural alloy for aircraft fuselages and aviation components.

Question 13

Why is high viscosity index desirable in lubricants?

Accepted Answer

Option A: Ensures stable lubrication across different temperatures. The Viscosity Index (VI) is a dimensionless measure of the rate of change of lubricant viscosity with temperature; a High Viscosity Index means minimal change in viscosity across operating temperature extremes, ensuring stable hydrodynamic lubrication.

Question 14

Which of the following is an example of a thermosetting plastic?

Accepted Answer

Option D: Bakelite. Bakelite (phenol-formaldehyde cross-linked resin) is a classic Thermosetting Plastic that undergoes irreversible chemical cross-linking upon heating and cannot be remolded or melted (Polyethylene, PVC, Polystyrene are thermoplastics).

Question 15

Match the different types of wooden joints with their corresponding description:
Wooden Joints:
i. Lap Joint
ii. Dovetail Joint
iii. Rabbet Joint
iv. Butt Joint

Description:
1. A groove cut into one piece to fit another
2. Interlocking wedge-shaped cuts for high strength
3. Two pieces of wood are joined end-to-end
4. Overlapping joint for increased surface contact.

Choose the correct option:

Accepted Answer

Option A: i-4, ii-2, iii-1, iv-3. i -> 4 (Lap Joint: overlapping wooden pieces for bonded contact area), ii -> 2 (Dovetail Joint: trapezoidal interlocking fan/wedge cuts resisting tensile pulling), iii -> 1 (Rabbet Joint: recess/groove cut into edge), iv -> 3 (Butt Joint: square ends joined end-to-end or edge-to-face). Correct match: i-4, ii-2, iii-1, iv-3.

Question 16

Which statement is NOT correct about advantages of Gas Metal Arc Welding (GMAW / MIG)?

Accepted Answer

Option D: GMAW is used to weld metals having high melting points like tungsten.. Statement D is NOT correct: In GMAW (MIG/MAG), a consumable continuously fed wire electrode melts to form the weld pool; Tungsten is a refractory non-consumable electrode used in GTAW/TIG welding, NOT welded as a base metal via GMAW.

Question 17

Which type of battery is commonly used in traditional automobiles?

Accepted Answer

Option A: Flooded lead-acid battery. Traditional internal combustion engine automobiles standardly utilize a 12-volt Flooded Lead-Acid Starter-Lighting-Ignition (SLI) Battery due to its high surge cranking current capacity, reliability, and cost-effectiveness.

Question 18

Which of the following is true about 3-phase power supply compared to single-phase power?

Accepted Answer

Option B: It provides a smoother and more continuous flow of power. A 3-Phase AC power supply delivers a constant, non-pulsating instantaneous power ($P = \sqrt{3} V_L I_L \cos\phi$) with a smoother and more continuous flow of power and rotating magnetic fields, requiring less conductor material than equivalent single-phase systems.

Question 19

Which of the following statements is/are correct regarding Radial Drilling Machine?
1. It is used for drilling holes in large and heavy workpieces.
2. The radial arm allows the drill head to move horizontally and vertically for flexible positioning.
3. It is ideal for precision drilling, reaming, and tapping operations.
4. The machine is suitable for materials like hardened steel, ceramics, and alloys.
Choose the correct statement:

Accepted Answer

Option B: 1, 2 and 3. Statements 1, 2, and 3 are correct: Radial drill presses accommodate heavy stationary castings (1), feature a swinging/elevating radial arm for multi-position hole drilling without moving the job (2), and perform drilling, boring, reaming, and tapping (3). (Statement 4 is false as standard HSS/carbide radial drills cannot machine non-conductive brittle ceramics). Correct: 1, 2 and 3.

Question 20

Which type of refrigerant is commonly used in modern air conditioners?

Accepted Answer

Option C: R-410A. Modern residential and commercial split air conditioning systems standardly use eco-friendly hydrofluorocarbon blends such as R-410A (Puron - a 50/50 blend of R-32 and R-125) or pure R-32 having zero Ozone Depletion Potential (ODP).

Question 21

Which of the following is NOT a characteristic of DC fuses?

Accepted Answer

Option D: Operates without any risk of arc formation in all conditions. Statement D is NOT a characteristic: In DC circuits, current does not naturally pass through a zero-crossing (unlike AC); hence, DC fault interruption inherently creates severe persistent electric arcs requiring specialized arc-quenching media (it CANNOT operate 'without any risk of arc formation').

Question 22

Which of the following is a key advantage of using superimposed dimensioning in technical drawings?

Accepted Answer

Option C: It simplifies complex drawings by grouping dimensions from a common datum.. Superimposed Running Dimensioning (progressive dimensioning from a single common origin/datum line) simplifies crowded engineering drawings, saves drawing space, and eliminates clutter from multiple parallel dimension lines.

Question 23

A scale has an RF of 1:400. If an actual distance of 8 km is to be represented, what will be the length of the scaled drawing?

Accepted Answer

Option B: 20 meters. Representative Fraction $	ext{RF} = \frac{	ext{Length on drawing}}{	ext{Actual distance}} \implies 	ext{Drawing Length} = 	ext{RF} 	imes 	ext{Actual Distance} = \frac{1}{400} 	imes 8	ext{ km} = \frac{8,000	ext{ m}}{400} = 20	ext{ meters}$. Choice B.

Question 24

Which of the following correctly matches the methods of development of surfaces with their descriptions?
Methods of Development:
i. Parallel Line Development
ii. Radial Line Development
iii. Triangulation Development
iv. Approximate Development

Description:
1. Used for objects with complex curved surfaces, where accuracy is less critical.
2. Used for irregular objects by dividing the surface into triangles.
3. Used for objects with parallel generating lines, such as cylinders and prisms.
4. Used for objects with a single central point, such as cones and pyramids.

Choose the correct option:

Accepted Answer

Option C: i-3, ii-4, iii-2, iv-1. i -> 3 (Parallel Line: prisms, cylinders with parallel edges), ii -> 4 (Radial Line: pyramids, cones converging to single apex vertex), iii -> 2 (Triangulation: transition pieces and irregular shapes divided into planar triangles), iv -> 1 (Approximate method: doubly curved surfaces like spheres/paraboloids). Correct match: i-3, ii-4, iii-2, iv-1.

Question 25

Which of the following statements about Lewis Foundation Bolt is/are correct?
1. Lewis foundation bolts are made from strong materials like stainless steel and carbon steel.
2. It has a tapered body which comes with grooves on all sides of its body and a square or rectangular cross-section.
3. They offer durability, longevity, and resistance to environmental factors.
4. Available in various sizes, including 25mm, they are used in different structural projects.
Choose the correct option:

Accepted Answer

Option C: 1, 2 and 3. Statements 1, 2, and 3 accurately describe the Lewis Foundation Bolt: Made of forged carbon steel (1), featuring a rectangular cross-section with one side tapered to receive a locking iron key for easy removal and heavy machine foundation anchoring (2), providing high strength and durability (3). Correct: 1, 2 and 3.

Question 26

How is the knuckle pin secured in a knuckle joint?

Accepted Answer

Option B: Using a split pin or taper pin. In a standard Knuckle Joint assembly, the cylindrical knuckle pin passes through the eye end and fork end, and is secured at the bottom by a solid collar and a Split Pin (cotter pin) inserted through a transverse cross-hole.

Question 27

Flange couplings are typically used to connect shafts that are:

Accepted Answer

Option C: Perfectly aligned and collinear. A Rigid Flange Coupling consists of two cast-iron flanged hubs keyed to shaft ends and bolted together, requiring the two shafts to be in Perfect Axial Collinear Alignment without misalignment.

Question 28

In a riveted joint, what type of failure occurs when the rivet diameter is smaller than necessary?

Accepted Answer

Option B: Shearing of the rivet. When the rivet diameter is undersized, the cross-sectional shear area of the rivet shank ($A = rac{\pi}{4}d^2$) is insufficient to withstand the applied tensile shear force, causing catastrophic Shearing of the Rivet across the interface of the plates.

Question 29

Select the most appropriate option to substitute the underlined segment in the given sentence:
The committee has submitted their report on the environmental impact.

Accepted Answer

Option B: has submitted its. When a collective noun ('committee') acts as a unified single body, it takes a singular verb and the neuter singular possessive pronoun 'its' ('has submitted its report'). Choice B.

Question 30

Identify the part of the sentence that contains a grammatical error:
If I was the president, I would implement that policy.

Accepted Answer

Option A: If I was. In hypothetical, unreal, or contrary-to-fact conditional clauses (Second Conditional / Subjunctive Mood), the verb 'were' must be used for all subjects: 'If I were the president' (not 'was'). Error is in part A.

Question 31

Given below are five scattered segments of a sentence. Indicate the correct sequence which correctly assembles the segments and completes the sentence:
P. knowing it was
Q. Children reluctantly
R. left the playground,
S. time to head home.
The correct sequence should be:

Accepted Answer

Option D: QRPS. Subject: 'Children reluctantly' (Q) $->$ Verb phrase: 'left the playground,' (R) $->$ Participle clause: 'knowing it was' (P) $->$ Complement: 'time to head home.' (S). Correct sequence: Q-R-P-S (QRPS). Choice D.

Question 32

Fill in the blanks with correct pair of words:
The action movie featured a ________ between two characters, each wielding weapons with ________ functionalities.

Accepted Answer

Option A: duel, dual. 'Duel' refers to a formal combat/fight between two persons, whereas 'Dual' means having two parts, functions, or aspects ('a duel between two characters with dual functionalities'). Choice A.

Question 33

What does the idiom "spill the beans" mean?

Accepted Answer

Option B: To reveal a secret. The idiom 'spill the beans' means to disclose, divulge, or reveal secret, confidential, or premature information.

Question 34

Choose the correct active voice conversion of the following sentence:
"The project had been completed by the team before the deadline."

Accepted Answer

Option D: The team had completed the project before the deadline.. Passive: 'had been completed' (Past Perfect Passive) $->$ Active: 'The team had completed the project before the deadline' (Past Perfect Active). Choice D.

Question 35

Identify the correct indirect speech conversion of the following sentence:
She said, "Had I known about the meeting, I would have attended it."

Accepted Answer

Option A: She said that if she had known about the meeting, she would have attended it.. Direct: Inverted third conditional clause 'Had I known... I would have attended'. Indirect: 'She said that if she had known about the meeting, she would have attended it.' Choice A.

Question 36

Identify the correct verb form to complete the sentence:
She ________ in the choir since she was six years old.

Accepted Answer

Option B: has been singing. With the time preposition 'since' indicating an action that started in the past and continues into the present, the Present Perfect Continuous tense ('has been singing') is grammatically required.

Question 37

Find the coefficient of the term $x^3 y^2 z^4$ in the expansion of $(x + y + z)^9$:

Accepted Answer

Option C: 1260. Using the Multinomial Theorem: The coefficient of $x^a y^b z^c$ in $(x + y + z)^n$ (where $a + b + c = n = 9$) is given by: $\frac{n!}{a! b! c!} = \frac{9!}{3! 2! 4!} = \frac{362880}{6 	imes 2 	imes 24} = \frac{362880}{288} = 1260$. Choice C.

Question 38

Find the value of the following term: $\sin(	heta + 45^\circ) - \cos(	heta - 45^\circ)$

Accepted Answer

Option B: 0. Using trigonometric co-function identities: $\cos(A) = \sin(90^\circ - A)$. Here $\cos(	heta - 45^\circ) = \sin(90^\circ - (	heta - 45^\circ)) = \sin(135^\circ - 	heta)$. Since $\sin(180^\circ - x) = \sin(x)$, $\sin(135^\circ - 	heta) = \sin(180^\circ - (135^\circ - 	heta)) = \sin(45^\circ + 	heta) = \sin(	heta + 45^\circ)$. Thus, $\sin(	heta + 45^\circ) - \sin(	heta + 45^\circ) = 0$. Choice B.

Question 39

Consider the circle $x^2 + y^2 - 4x + 6y + 9 = 0$ and the lines $L_1: x + 2y = 1$, $L_2: 2x - y + 3 = 0$. Then which of the following is correct?
I. The circle's center is $(2, -3)$ and its radius is 2.
II. L1 does not intersect the circle.
III. The angle between the lines L1 and L2 is 45°.
Choose the correct option:

Accepted Answer

Option A: Only (I) and (II) are true.. 1. Circle: $(x-2)^2 + (y+3)^2 = 4 + 9 - 9 = 4 = 2^2 \implies$ Center $(2, -3)$, Radius $R = 2$ (I is True). 2. Perpendicular distance of $L_1 (x + 2y - 1 = 0)$ from $(2, -3)$: $d = \frac{|2 + 2(-3) - 1|}{\sqrt{1^2 + 2^2}} = \frac{|-5|}{\sqrt{5}} = \sqrt{5} \approx 2.236 > 2 (R)$, so $L_1$ does not intersect the circle (II is True). 3. Slopes of lines: $m_1 = -1/2, m_2 = 2 \implies m_1 m_2 = -1$, meaning lines are perpendicular ($90^\circ$, not $45^\circ$, so III is False). Correct: Only (I) and (II) are true.

Question 40

Evaluate the integral $\int_0^{\pi/2} \cos^2 x\,dx$:

Accepted Answer

Option B: pi / 4. Using identity $\cos^2 x = \frac{1 + \cos 2x}{2}$: $\int_0^{\pi/2} \cos^2 x\,dx = \left[ \frac{x}{2} + \frac{\sin 2x}{4} \right]_0^{\pi/2} = \left( \frac{\pi/2}{2} + \frac{\sin\pi}{4} \right) - (0) = \frac{\pi}{4}$. Choice B.

Question 41

This managerial function deals with placing the right things at right places / right people in right jobs:

Accepted Answer

Option D: Organising. Organising as a core managerial function arranges, groups, and allocates physical, financial, and structural resources systematically into orderly positions (and Staffing assigns right persons to right jobs).

Question 42

Which among the following is a force to drive an employee/worker to action?

Accepted Answer

Option C: Motivation. Motivation (derived from *motive*) is the internal psychological driving force that energizes, directs, and sustains goal-oriented human behavior and productivity in the workplace.

Question 43

Which among the following is NOT a barrier to effective organisational communication?

Accepted Answer

Option A: Feedback. Feedback is a vital facilitator and constructive channel that confirms understanding and closes the communication loop; Ambiguity, Distortions, and Lack of Trust are communication barriers.

Question 44

Which level of Maslow's need Hierarchy Theory of Motivation of individuals in a work environment deals with the Basic Needs of food, water and shelter of the individuals?

Accepted Answer

Option B: Physiological. In Abraham Maslow's Hierarchy of Needs, the foundational first-tier level comprises Physiological Needs—the fundamental biological biological requirements for human survival including food, water, air, shelter, and sleep.

Question 45

Which of the following terms best describes the grapevine as a communication pattern?

Accepted Answer

Option B: Informal. The 'Grapevine' is the informal, unofficial, peer-to-peer interpersonal communication network in an organization that operates outside formal hierarchy and authority channels.

Question 46

Which organisation supports entrepreneurship and entrepreneurs in India?

Accepted Answer

Option D: All of the above. All listed statutory bodies actively support Indian industrial entrepreneurship: NEDB coordinates policy, EPC facilitates export trade, and SISI (MSME Development Institutes) provides technical and financial handholding. Choice D.

Question 47

Human Resource Management (HRM) is:

Accepted Answer

Option A: A Staff Function. In corporate organizational design, Human Resource Management operates primarily as a Staff Function—providing expert advisory, talent acquisition, legal compliance, and auxiliary support services to line management executives.

Question 48

Time Management is best demonstrated by:

Accepted Answer

Option B: First Things First - Prioritizing Tasks to Focus on The Most Important Ones First. Effective Time Management (Stephen Covey's Quadrant II matrix) is best demonstrated by the 'First Things First' principle—categorizing and prioritizing tasks by importance and urgency rather than working haphazardly.

Question 49

If the water boils at 123°C inside a pressure cooker, what is the absolute pressure inside it? Given that water boils at 100°C under a pressure of 100 kPa.

Accepted Answer

Option D: 108.17 kPa / 218 kPa. From steam tables and the Clausius-Clapeyron relation, the saturation vapor pressure of water at $123^\circ	ext{C}$ is approximately $218.5	ext{ kPa}$ (or $pprox 108.17	ext{ kPa}$ excess/gauge conversion under empirical exam options). Choice D.

Question 50

Which of the following sets consists entirely of intensive properties?

Accepted Answer

Option A: Pressure, temperature, density, specific volume. Intensive properties are physical properties independent of the size or mass of the system: Pressure ($P$), Temperature ($T$), Density ($ho$), and Specific Volume ($v = V/m$) are all intensive. (Volume, Energy, and Heat are extensive). Choice A.

Question 51

Which of the following parameters remains constant during the ideal throttling process?

Accepted Answer

Option D: Enthalpy. An ideal Throttling Process (Joule-Thomson expansion through an uninsulated porous plug or partly closed valve with no work or heat transfer) is an Isenthalpic Process ($h_1 = h_2$, Enthalpy remains constant).

Question 52

A refrigerator works on a reversed Carnot cycle between 900 K and 300 K. If heat is extracted from the low-temperature space at a rate of 3 kJ/s, determine the power needed to operate the refrigerator:

Accepted Answer

Option C: 6 kW. Coefficient of Performance of reversed Carnot refrigerator: $	ext{COP}_R = \frac{T_L}{T_H - T_L} = \frac{300}{900 - 300} = \frac{300}{600} = 0.5$. Power input required: $W = \frac{Q_L}{	ext{COP}_R} = \frac{3	ext{ kJ/s}}{0.5} = 6	ext{ kW}$. Choice C.

Question 53

If a heat engine produces an output of 3 kW with an input of 10,000 J/s, what is the thermal efficiency of the engine?

Accepted Answer

Option D: 30 %. Work output $W_{net} = 3	ext{ kW} = 3000	ext{ J/s}$. Heat input $Q_{in} = 10,000	ext{ J/s}$. Thermal Efficiency $\eta = \frac{W_{net}}{Q_{in}} 	imes 100 = \frac{3000}{10000} 	imes 100 = 30\%$. Choice D.

Question 54

A heat pump is a device that:

Accepted Answer

Option A: Provides heat to a room by extracting it from the surroundings with work supplied. A Heat Pump operates on a reversed thermodynamic cycle that extracts heat from a low-temperature cold reservoir (external ambient surroundings) and discharges it into a high-temperature conditioned space by consuming external mechanical/electrical work.

Question 55

In a centrifugal air compressor, the pressure generated depends on:

Accepted Answer

Option D: All of the above. Pressure rise across a centrifugal compressor stage is governed by Euler's turbomachine equation and depends on Impeller Tip Speed ($u_2^2$), gas polytropic compression index, inlet density, and blade geometry $\implies$ All of the above.

Question 56

The volumetric efficiency of a reciprocating compressor depends upon:
I. Pressure ratio
II. Clearance volume
III. Index of expansion
Choose the correct option:

Accepted Answer

Option B: I, II, and III. Volumetric efficiency formula: $\eta_v = 1 - C\left[\left(\frac{P_2}{P_1}\right)^{1/n} - 1\right]$, where $C = V_c / V_s$ is the Clearance Ratio (II), $P_2/P_1$ is the Pressure Ratio (I), and $n$ is the Polytropic Expansion Index (III). Thus, it depends upon I, II, and III. Choice B.

Question 57

For the same compression ratio and identical heat input, what is the correct order of increasing thermal efficiencies among the Otto, Diesel, and Dual cycles?

Accepted Answer

Option D: Diesel, Dual, Otto. For the same compression ratio ($r$) and identical heat addition ($Q_{in}$): Constant-volume heat addition in the Otto cycle occurs at maximum temperature and pressure, yielding the highest efficiency: $\eta_{	ext{Diesel}} < \eta_{	ext{Dual}} < \eta_{	ext{Otto}}$. In increasing order: Diesel, Dual, Otto. Choice D.

Question 58

Select the option that correctly matches the items given in List I to those given in List - II:
List -I (Processes of Cycle):
(w) Two isothermal and two adiabatic
(x) Two isothermal and two constant volumes
(y) Two adiabatic and two constant volumes
(z) Two adiabatic and two constant pressure

List -II (Name of Cycle):
(i) Joule cycle
(ii) Otto Cycle
(iii) Carnot cycle
(iv) Stirling cycle

Choose the correct option:

Accepted Answer

Option A: (w)- (iii), (x)-(iv), (y)-(ii), (z)-(i). w -> iii (Carnot cycle: 2 isothermal + 2 reversible adiabatic/isentropic), x -> iv (Stirling cycle: 2 isothermal + 2 constant volume/isochoric), y -> ii (Otto cycle: 2 isentropic + 2 constant volume), z -> i (Joule / Brayton cycle: 2 isentropic + 2 constant pressure/isobaric). Correct match: (w)-(iii), (x)-(iv), (y)-(ii), (z)-(i).

Question 59

The third unknown force in a coplanar concurrent force system in equilibrium can be determined best by:

Accepted Answer

Option A: Triangle of forces. According to the Triangle Law of Forces (and Lami's Theorem), if three coplanar concurrent forces acting on a particle are in static equilibrium, they can be represented completely in magnitude and direction by the three sides of a closed triangle taken in order.

Question 60

If two forces of 7N and 8N act at an angle of 60°, the resultant force will be:

Accepted Answer

Option B: 13 N. Using the parallelogram law of vector addition: $R = \sqrt{P^2 + Q^2 + 2PQ\cos	heta} = \sqrt{7^2 + 8^2 + 2(7)(8)\cos 60^\circ} = \sqrt{49 + 64 + 2(56)(0.5)} = \sqrt{113 + 56} = \sqrt{169} = 13	ext{ N}$. Choice B.

Question 61

The angle of friction is equivalent to the:

Accepted Answer

Option C: Angle of an inclined plane when a body tends to slide down. The Angle of Friction ($\lambda = 	an^{-1}\mu$) is mathematically and physically identical to the Angle of Repose ($	heta$)—the maximum inclination angle of a plane at which a resting body is on the verge of sliding down under gravity alone.

Question 62

Friction force (F), normal reaction (N) and coefficient of friction ($\mu$) are related as:

Accepted Answer

Option B: F = uN. According to Coulomb's Law of Dry Friction, the maximum limiting static friction force is directly proportional to the normal reaction force: $F = \mu N$ (or $\mu = F/N$). Option B.

Question 63

If the coefficient of friction $\mu = \frac{1}{\sqrt{3}}$, then the angle of friction ($\lambda$) is:

Accepted Answer

Option D: 30°. Angle of friction $\lambda = 	an^{-1}(\mu) = 	an^{-1}\left(\frac{1}{\sqrt{3}}ight) = 30^\circ$. Choice D.

Question 64

When a solid shaft is subjected to torsion, the shear stress generated at the centre of the shaft is:

Accepted Answer

Option B: Zero. From the torsion formula $\frac{	au}{r} = \frac{T}{J} \implies 	au = \frac{T \cdot r}{J}$. At the geometric center axis of a solid circular shaft, the radial distance $r = 0$, so the torsional shear stress is identically Zero (and maximum at the outer surface $r = R$).

Foreman2025

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JKSSB — Foreman (2025)

A scientist proposes that the speed V of a wave traveling along a stretched string depends on the tension in the string T and the linear mass density of the string μ\muμ. Using dimensional analysis, derive the possible relation between V, T, and μ\muμ:

What is the effect of increasing the banking angle of a road?

Match the following modes of heat transfer with their examples:Modes of Heat Transfer:i. Conductionii. Convectioniii. RadiationExamples:1. Boiling water in a pot2. Metal spoon handle heating up in hot soup3. Feeling the warmth of the SunChoose the correct statement:

Which of the following is NOT a primary reason for the decrease in resistance of a semiconductor with an increase in temperature?

How does the cross-sectional area of solenoids affect the coupling coefficient (K)?

Which of the following statements about a PN junction diode is incorrect?

Which of the following is NOT a favorable condition for forming an ionic bond?

Which of the following statements is NOT correct regarding the importance of pH in everyday life?

Which of these alloys is lightweight and commonly used in aircraft manufacturing?

Why is high viscosity index desirable in lubricants?

Which of the following is an example of a thermosetting plastic?

Which statement is NOT correct about advantages of Gas Metal Arc Welding (GMAW / MIG)?

Which type of battery is commonly used in traditional automobiles?

Which of the following is true about 3-phase power supply compared to single-phase power?

Which type of refrigerant is commonly used in modern air conditioners?

Which of the following is NOT a characteristic of DC fuses?

Which of the following is a key advantage of using superimposed dimensioning in technical drawings?

A scale has an RF of 1:400. If an actual distance of 8 km is to be represented, what will be the length of the scaled drawing?

How is the knuckle pin secured in a knuckle joint?

Flange couplings are typically used to connect shafts that are:

In a riveted joint, what type of failure occurs when the rivet diameter is smaller than necessary?

Select the most appropriate option to substitute the underlined segment in the given sentence:The committee has submitted their report on the environmental impact.

Identify the part of the sentence that contains a grammatical error:If I was the president, I would implement that policy.

Given below are five scattered segments of a sentence. Indicate the correct sequence which correctly assembles the segments and completes the sentence:P. knowing it wasQ. Children reluctantlyR. left the playground,S. time to head home.The correct sequence should be:

Fill in the blanks with correct pair of words:The action movie featured a ________ between two characters, each wielding weapons with ________ functionalities.

What does the idiom "spill the beans" mean?

Choose the correct active voice conversion of the following sentence:"The project had been completed by the team before the deadline."

Identify the correct indirect speech conversion of the following sentence:She said, "Had I known about the meeting, I would have attended it."

Identify the correct verb form to complete the sentence:She ________ in the choir since she was six years old.

Find the coefficient of the term x3y2z4x^3 y^2 z^4x3y2z4 in the expansion of (x+y+z)9(x + y + z)^9(x+y+z)9:

Find the value of the following term: sin⁡(θ+45∘)−cos⁡(θ−45∘)\sin(\theta + 45^\circ) - \cos(\theta - 45^\circ)sin(θ+45∘)−cos(θ−45∘)

Evaluate the integral ∫0π/2cos⁡2x dx\int_0^{\pi/2} \cos^2 x\,dx∫0π/2​cos2xdx:

This managerial function deals with placing the right things at right places / right people in right jobs:

Which among the following is a force to drive an employee/worker to action?

Which among the following is NOT a barrier to effective organisational communication?

Which level of Maslow's need Hierarchy Theory of Motivation of individuals in a work environment deals with the Basic Needs of food, water and shelter of the individuals?

Which of the following terms best describes the grapevine as a communication pattern?

Which organisation supports entrepreneurship and entrepreneurs in India?

Human Resource Management (HRM) is:

Time Management is best demonstrated by:

If the water boils at 123°C inside a pressure cooker, what is the absolute pressure inside it? Given that water boils at 100°C under a pressure of 100 kPa.

Which of the following sets consists entirely of intensive properties?

Which of the following parameters remains constant during the ideal throttling process?

A refrigerator works on a reversed Carnot cycle between 900 K and 300 K. If heat is extracted from the low-temperature space at a rate of 3 kJ/s, determine the power needed to operate the refrigerator:

If a heat engine produces an output of 3 kW with an input of 10,000 J/s, what is the thermal efficiency of the engine?

A heat pump is a device that:

In a centrifugal air compressor, the pressure generated depends on:

The volumetric efficiency of a reciprocating compressor depends upon:I. Pressure ratioII. Clearance volumeIII. Index of expansionChoose the correct option:

For the same compression ratio and identical heat input, what is the correct order of increasing thermal efficiencies among the Otto, Diesel, and Dual cycles?

The third unknown force in a coplanar concurrent force system in equilibrium can be determined best by:

If two forces of 7N and 8N act at an angle of 60°, the resultant force will be:

The angle of friction is equivalent to the:

Friction force (F), normal reaction (N) and coefficient of friction (μ\muμ) are related as:

If the coefficient of friction μ=13\mu = \frac{1}{\sqrt{3}}μ=3​1​, then the angle of friction (λ\lambdaλ) is:

When a solid shaft is subjected to torsion, the shear stress generated at the centre of the shaft is:

The torsion formula is applicable only up to:

The positive plate of a lead-acid battery contains:

Determine the number of poles needed when the frequency is 50 Hz and the motor synchronous speed is 1000 rpm:

The specific gravity of the electrolyte in a fully charged automobile battery is approximately:

The most commonly used sensor for temperature measurement in vehicles is:

The effect that occurs when a transverse magnetic field is applied to a current-carrying conductor plate is known as:

In a DC generator, the magnetic field is produced in the:

The Seebeck effect is used in:

Which type of motor is commonly used in modern electric vehicles (EVs)?

The motor commonly used for elevators is generally:

What is the correct order of the various steps involved in cold tyre retreading?I. Tread mountingII. Thermal curingIII. Inspection of casingIV. BuffingChoose the correct option:

What is the maximum addressing capacity of the Intel 8085 microprocessor?

A bipolar junction transistor schematic symbol with the emitter arrow pointing outwards (away from the base) represents which device?

What is a Miniature Circuit Breaker (MCB)?

Which of the following fuels has the highest resistance to detonation (highest octane rating)?

The calorific value of gaseous fuels is typically expressed in:

What is the total energy supplied per minute if a 4-stroke IC engine consumes fuel at a rate of 0.1 kg per minute, with a fuel calorific value of 40,000 kJ/kg?

The type of lubrication system used in aircraft engines is:

Which of the below statements is/are correct regarding engine oil?I. The viscosity should be low enough to allow smooth pumping and minimize cranking resistance.II. It should maintain a sufficiently high viscosity at elevated temperatures while having low volatility.Choose the correct statement:

Choose the INCORRECT statement from the following regarding an air-cooled IC engine:

Which of the following is a desirable engine coolant property?

Which of the following is NOT a part of the automotive chassis?

A scientist proposes that the speed V of a wave traveling along a stretched string depends on the tension in the string T and the linear mass density of the string $\mu$ . Using dimensional analysis, derive the possible relation between V, T, and $\mu$ :

Match the following modes of heat transfer with their examples:
Modes of Heat Transfer:
i. Conduction
ii. Convection
iii. Radiation

Examples:
1. Boiling water in a pot
2. Metal spoon handle heating up in hot soup
3. Feeling the warmth of the Sun

Choose the correct statement:

Select the most appropriate option to substitute the underlined segment in the given sentence:
The committee has submitted their report on the environmental impact.

Identify the part of the sentence that contains a grammatical error:
If I was the president, I would implement that policy.

Given below are five scattered segments of a sentence. Indicate the correct sequence which correctly assembles the segments and completes the sentence:
P. knowing it was
Q. Children reluctantly
R. left the playground,
S. time to head home.
The correct sequence should be:

Fill in the blanks with correct pair of words:
The action movie featured a between two characters, each wielding weapons with functionalities.

Choose the correct active voice conversion of the following sentence:
"The project had been completed by the team before the deadline."

Identify the correct indirect speech conversion of the following sentence:
She said, "Had I known about the meeting, I would have attended it."

Identify the correct verb form to complete the sentence:
She ________ in the choir since she was six years old.

Find the coefficient of the term $x^3 y^2 z^4$ in the expansion of $(x + y + z)^9$ :

Find the value of the following term: $\sin(\theta + 45^\circ) - \cos(\theta - 45^\circ)$

Evaluate the integral $\int_0^{\pi/2} \cos^2 x\,dx$ :

The volumetric efficiency of a reciprocating compressor depends upon:
I. Pressure ratio
II. Clearance volume
III. Index of expansion
Choose the correct option:

Friction force (F), normal reaction (N) and coefficient of friction ( $\mu$ ) are related as:

If the coefficient of friction $\mu = \frac{1}{\sqrt{3}}$ , then the angle of friction ( $\lambda$ ) is:

What is the correct order of the various steps involved in cold tyre retreading?
I. Tread mounting
II. Thermal curing
III. Inspection of casing
IV. Buffing
Choose the correct option:

Which of the below statements is/are correct regarding engine oil?
I. The viscosity should be low enough to allow smooth pumping and minimize cranking resistance.
II. It should maintain a sufficiently high viscosity at elevated temperatures while having low volatility.
Choose the correct statement:

What is the correct sequence of force transmission in a brake system with a vacuum servo mechanism when the brake pedal is pressed?
I. Vacuum servo mechanism
II. Brake lines
III. Brake pedal
IV. Brake pads
V. Master cylinder
Choose the correct option:

Which one of the following pairs is/are NOT correctly matched?
I. Clutch - Diaphragm spring
II. Differential - Hypoid gear
III. Steering gearbox - Rack and pinion
IV. Transmission gearbox - Bevel gears
Choose the correct option:

Which of the below statements is/are correct regarding tyre wear?
I. An under-inflated tyre wears the most at the centre part of the tread.
II. An over-inflated tyre wears the most near the edges of the tread.
Choose the correct statement:

The natural frequency $\omega_n$ of the spring-mass system shown (two parallel springs of $k/2$ connected in series with a spring of $k$ attached to mass $m$ ) is: