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Past Questions — 2016
Petrol engine works on
A)
Diesel cycle
B)
Dual cycle
C)
Otto cycle
D)
None of these
A petrol engine is a spark-ignition engine, and its ideal thermodynamic cycle is the Otto cycle. Diesel engines work on the Diesel cycle, while the Dual cycle is a combination of Otto and Diesel characteristics and is not the standard cycle for petrol engines. Therefore, the correct answer is Otto cycle.
The octane rating of petrol commercially available is usually
A)
85-90
B)
90-100
C)
100-110
D)
110 - 125
The octane number of commercially available petrol is usually in the range of about 85 to 90. This reflects its anti-knock quality for spark-ignition engines. Options (b), (c), and (d) are too high for ordinary commercial petrol; such values correspond to premium or highly specialized fuels, not the usual retail petrol grade.
Which one is not the method of cooling an I.C. engine?
A)
Air cooling
B)
Oil cooling
C)
Water cooling
D)
Steam cooling
I.C. engines are commonly cooled by air cooling, water cooling, and sometimes oil cooling. Steam cooling is not used as a standard method of cooling in I.C. engines. Therefore, the correct answer is Steam cooling.
The principle of a radiator of an engine cooling system is to
A)
Act as a reservoir for the water
B)
Cause heat flow by convection currents
C)
Spread out the hot water over a large area
D)
Increase the air speed as it flows over the hot surface
A radiator removes heat from the engine coolant by exposing the hot water/coolant to a large surface area so that heat can be transferred to the surrounding air. This is the basic principle of a radiator. Option (a) describes a header tank/reservoir, not the main cooling principle. Option (b) is incomplete because convection helps, but the radiator’s key principle is increasing heat transfer area. Option (d) refers to the effect of a fan or air flow, not the radiator itself.
In a four-stroke engine, each cylinder has
A)
One valve
B)
Two valves
C)
Three valves
D)
Four valves
In a basic four-stroke engine, each cylinder generally has two valves: one inlet valve and one exhaust valve. The inlet valve admits the air-fuel mixture (or air in diesel engines), and the exhaust valve removes the burnt gases. Hence, the correct answer is Two valves. The other options are not the standard basic configuration.
An engine has a clearance volume of 100cm³ and swept volume of 800cm³. The compression ratio is
A)
7:1
B)
9:1
C)
10:1
D)
8:1
Compression ratio = (Swept volume + Clearance volume) / Clearance volume. Here, = (800 + 100) / 100 = 900 / 100 = 9:1. So the correct calculated value is 9:1, which corresponds to option (b).
Mark the one alternative that is nearest in meaning to the word - Nullify
A)
Impress
B)
No effect
C)
Seclude
D)
Astound
“Nullify” means to make something invalid, cancel it out, or have no effect. Among the given options, “No effect” is the nearest in meaning. The other options are unrelated: “Impress” means influence favorably, “Seclude” means isolate, and “Astound” means surprise greatly.
The resultant upward thrust experienced by a body when immersed in the fluid is known as
A)
Equilibrium of floating bodies
B)
Buoyancy
C)
Weight ofa body
D)
None of these
The upward force exerted by a fluid on a body immersed in it is called buoyancy or buoyant force. This is the resultant upward thrust mentioned in the question. Option (a) is a condition related to floating bodies, (c) is unrelated, and (d) is incorrect because the correct term is given in (b).
Which one is not components of cost?
A)
Prime cost
B)
Factory cost & Office cost
C)
Total cost
D)
None of these
In cost accounting, the main components of cost are prime cost, factory/works cost, office cost, and total cost. Since all options (a), (b), and (c) are components of cost, the correct choice for 'which one is not components of cost' is 'None of these'.
Indirect Expenses is known as overhead charges, on-cost, burden or indirect charges. Which one is not included in classification of Indirect Expenses?
A)
Factory expenses
B)
Administration & Selling expenses
C)
Distribution expenses
D)
None of these
Indirect expenses (overheads) are commonly classified into factory/workshop expenses, administration expenses, selling expenses, and distribution expenses. Since all the options in (a), (b), and (c) are valid classes of indirect expenses, none of them is excluded. Therefore, the correct answer is (d) None of these.
A process, which can be reversed, cannot lead to the initial state of the system and the surroundings without external inputs, is
A)
Irreversible process
B)
Reversible process
C)
Constant process
D)
None of these
A reversible process is one that can be reversed at any stage, and both the system and surroundings can be restored to their initial states with no net change. The question states a process that cannot return the system and surroundings to the initial state without external input, which is the definition of an irreversible process. Hence, option (a) is correct. Option (b) is wrong because reversible processes are fully reversible. Option (c) is not a thermodynamic term here, and (d) is incorrect because (a) fits the statement.
“The law of conservation of energy, according to which the total energy of an isolated system in all its forms remains constant. For a closed system executing a cycle only through heat and work, the change in internal energy is zero”, known as
A)
Second Law of Thermodynamics
B)
Newton’s First Law of Motion
C)
First Law of Thermodynamics
D)
None of these
The statement describes conservation of energy and says that for a closed system undergoing a cycle, the change in internal energy is zero. This is exactly the First Law of Thermodynamics. The Second Law deals with direction of heat flow and entropy, while Newton’s First Law is about inertia, not thermodynamic energy conservation.
Which one is not included in major elements in Airconditioning?
A)
Compressor
B)
Condenser
C)
Evaporator
D)
None of these
In a basic air-conditioning/refrigeration system, the major elements are the compressor, condenser, evaporator, and expansion device. Since compressor, condenser, and evaporator are all included, none of the listed components is excluded. Therefore, the correct answer is 'None of these'.
As applied to steering, the abbreviation P.A.S. stands for
A)
Pump assisted system
B)
Pump aided steering
C)
Power activated system
D)
Power assisted steering
In automobile engineering, P.A.S. in the context of steering means Power Assisted Steering, which is a steering system that reduces driver effort by using hydraulic or electric assistance. The other options are not the standard expansion of P.A.S.
Cetane number of Diesel oil normally available in market is in the range
A)
45-50
B)
60-65
C)
75 - 80
D)
90-100
Cetane number indicates the ignition quality of diesel fuel. Commercial diesel normally available in the market has a cetane number in the range of about 45 to 50. Higher values mean better ignition quality, but extremely high values like 75–100 are not typical for ordinary diesel fuel.
Which one is not included in one of advantages of gas turbine?
A)
Braking is not effective due to very high speed
B)
Gas turbine is smooth in operation and continuous in performance
C)
It does not have reciprocating parts, hence it is easy to balance. It is free from vibration.
D)
None of these
Gas turbines are known for smooth, continuous operation, absence of reciprocating parts, easy balancing, and very low vibration. These are real advantages, matching options (b) and (c). Option (a) is not an advantage of gas turbines; in fact, ineffective braking due to high speed is a limitation, not a benefit. Therefore, the correct answer is (a).
In a centrifugal pump installation, while starting the position of delivery valve is
A)
Fully closed
B)
Fully open
C)
Half open
D)
More than half open
In a centrifugal pump, the delivery valve is kept fully closed at the time of starting. This reduces the starting load on the motor because the pump initially has to overcome only the inertia of the rotating parts and not the pressure head in the delivery pipe. After the pump reaches its normal speed, the delivery valve is opened धीरे-धीरे. Hence, option (a) is correct.
The standard gravity force on 1 kg is
A)
9.81 N
B)
10N
C)
9.81kg
D)
None of these
Standard gravity is the acceleration due to gravity at Earth's surface, taken as 9.81 m/s². The weight (gravity force) on a mass of 1 kg is F = m × g = 1 × 9.81 = 9.81 N. Option (b) is only an approximation, and (c) is incorrect because kg is a unit of mass, not force.
The measuring devices, which enable the position of a surface to be determined with respect to horizontal and are widely used for the static levelling of machinery and other equipment are
A)
Spirit levels
B)
Angle gauges
C)
Bevel protractor
D)
Sine bar
Spirit levels are measuring devices used to determine the position of a surface with respect to the horizontal. They are commonly used for static levelling of machinery and equipment. Angle gauges, bevel protractors, and sine bars are used for angle measurement, not for basic levelling.
Which of the following is not part of important factors which are required to be considered for selection of exact plant location?
A)
Easy access
B)
Availability of cheap, sufficient and suitable land
C)
Cost of material required for construction
D)
None of these
For selecting an exact plant location, important factors usually include easy access, availability of cheap, sufficient and suitable land, transportation, power, water, labour, and expansion scope. The cost of construction material is not a direct factor for choosing the plant site; it affects building cost, not location selection. So option (c) is the correct choice.
Which of the following does not form a part of equipments which are commonly used for electric arc welding?
A)
Electrode
B)
Gas
C)
AC or DC machine
D)
Cable lug
In electric arc welding, the common equipment includes an electrode, an AC or DC welding machine, welding leads/cables, and cable lugs/clamps. Gas is not a standard part of electric arc welding equipment; it is associated with gas welding or some special processes like TIG/MIG with shielding gas, not basic arc welding.
Grease cannot be used as a lubricant for the lubrication of
A)
Front wheel bearings
B)
Input shaft
C)
Coolant pump
D)
Transmission
Grease is suitable for slow-speed or moderately loaded parts like wheel bearings and some pumps, but it is not suitable for high-speed rotating shafts that need continuous oil circulation. The input shaft of a gearbox/transmission operates at high speed and needs oil lubrication, not grease. Hence, grease cannot be used for the lubrication of the input shaft. Front wheel bearings and coolant pump bearings may use grease, and transmission systems generally use gear oil.
The basic philosophy of quality control is
A)
Frequent inspection
B)
Both preventive & remedial
C)
Only preventive
D)
None of these
Quality control is not limited to checking defects after they occur. Its basic philosophy includes both preventive action (to avoid defects) and remedial action (to detect and correct defects if they occur). Hence, the best answer is 'Both preventive & remedial.' Frequent inspection is only a method, not the philosophy itself, and 'Only preventive' is incomplete.
Which of the following is/are not included in examples of machine element that employ friction for transfer of energy
A)
Belts
B)
Brakes
C)
Clutches
D)
Fuel tank
Machine elements that employ friction for transfer of energy include belts, brakes, and clutches. Belts transmit power by friction between the belt and pulley; brakes use friction to stop or control motion; clutches use friction to connect or disconnect rotating shafts. A fuel tank is not a machine element for friction-based energy transfer, so it is the correct choice.
The permissible maximum value of operating temperature for metal on metal material for the Brake is
A)
300°F
B)
400°F
C)
500°F
D)
600°F
For brake lining/friction materials, the permissible maximum operating temperature for metal-on-metal contact is typically taken as 400°F. Above this, friction characteristics deteriorate and wear increases rapidly. Hence, among the given options, 400°F is correct.