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Past Questions
The power (in horse power) transmitted by a belt drive is (T1 = belt tension in tight side, T2 = belt tension in loose side and V = belt speed)
A)
Power = ma
B)
Power = (T1 - T2)V / 550
C)
Power = (T1 + T2)V / 550
D)
None of these
In a belt drive, the useful power transmitted is the product of the effective driving force and belt speed. The effective driving force is the difference between the tight-side and loose-side tensions, i.e. (T1 - T2). So, power in ft-lb/s is (T1 - T2) × V. To convert to horsepower, divide by 550 since 1 hp = 550 ft-lb/s. Therefore, Power = (T1 - T2)V / 550. Option (c) is incorrect because the sum of tensions does not represent the driving force.
Which of the following does not form part of the effects which were obtained by Annealing process?
A)
Soften the steel
B)
Relieve internal stresses
C)
Improve machinability
D)
None of these
Annealing is a heat treatment process used to make steel softer, relieve internal stresses, and improve machinability. Since all three listed effects are obtained by annealing, none of the options (a), (b), or (c) is incorrect. Therefore, the correct answer is (d) None of these.
Which of the following is not basic area of inspection?
A)
Receiving inspection
B)
Final inspection
C)
Inprocess inspection
D)
Production
Basic areas of inspection in quality control generally include receiving inspection, in-process inspection, and final inspection. These are checkpoints used to ensure quality at different stages. Production itself is not an inspection area; it is the manufacturing/activity stage where inspection may take place.
The tools which are used for checking the size, shape and relative positions of various parts but not provided with graduated adjustable members are
A)
Gauges
B)
Measuring tape
C)
Laser
D)
None of these
Gauges are inspection tools used to check the size, shape, and relative positions of parts. They are generally not provided with graduated adjustable members. Measuring tape is a linear measuring instrument, and laser is used for measurement/alignment in different contexts, not for this definition.
A governor is a device
A)
to control temperature variation
B)
to slowdown the speed
C)
to control speed variation in an engine and controls the amount of fuel to an engine to match the load requirement to maintain in a specific speed
D)
None of these
A governor is used in engines to regulate the mean speed when the load changes. It does this by adjusting the fuel supply so that the engine maintains nearly constant speed. Option (a) is about temperature control, which is unrelated. Option (b) is incorrect because a governor does not simply slow down speed; it regulates it. Option (d) is wrong because option (c) correctly describes the function of a governor.
The maximum and minimum pressure in a plate clutch where the axial force is 1000 lb (the inside radius of contact is Ri =2 in, the outside radius is Ro = 4 in) is 39.8 psi and 19.9 psi respectively. If uniform wear is assumed, the Average pressure is
A)
29.85 psi
B)
26.5 psi
C)
19.9 psi
D)
None of these
For a plate clutch with **uniform wear**, pressure varies inversely with radius: p = C/r. Hence the maximum pressure occurs at the inner radius and the minimum pressure at the outer radius.
Given:
- p_max = 39.8 psi
- p_min = 19.9 psi
The average pressure for uniform wear is the mean of maximum and minimum pressures:
p_avg = (p_max + p_min) / 2 = (39.8 + 19.9) / 2 = 29.85 psi.
So the correct answer is **29.85 psi**.
Why others are incorrect:
- **26.5 psi** is not the arithmetic mean of the given pressures.
- **19.9 psi** is only the minimum pressure.
- **None of these** is incorrect because 29.85 psi is present in the options.
In factories the power or rotary motion from one shaft to another is usually transmitted by means of
A)
Crankshaft
B)
Belts or ropes
C)
H.T lines
D)
None of these
In factories, rotary motion from one shaft to another is commonly transmitted by flexible power transmission elements such as belts or ropes. They are widely used because they can transmit motion over some distance and tolerate slight misalignment. A crankshaft is used to convert reciprocating motion to rotary motion, not for shaft-to-shaft power transmission. H.T. lines are for electrical power transmission, not mechanical rotary motion.
The law, which states that strain is proportional to the stress producing it, is called
A)
Newton law
B)
Hooke’s law
C)
Goodman’s law
D)
None of these
The statement that strain is directly proportional to the stress producing it is Hooke’s law, valid within the elastic limit of a material. Newton’s law relates force and motion, and Goodman’s law is used in fatigue analysis, so they are not correct.
A process of generating a gear by means of a cutter that revolves and cuts like a milling cutter is called
A)
Rack cutter process
B)
Gear hobbing
C)
Slotting
D)
None of these
In gear hobbing, the gear blank is generated by a rotating cutter called a hob, which cuts continuously in a manner similar to a milling cutter. This is a standard gear manufacturing process based on generation. Rack cutter process uses a rack-type cutter, while slotting is a different machining process used mainly for internal surfaces and keyways. Therefore, the correct answer is Gear hobbing.
Which is not column & knee type milling machine?
A)
Hand milling machine
B)
Plain milling machine
C)
Triplex milling machine
D)
Vertical milling machine
Column-and-knee type milling machines include hand milling machines, plain milling machines, and vertical milling machines. A triplex milling machine is not a column-and-knee type; it is a special-purpose milling machine having three spindle heads for simultaneous machining.
A metal cannot exist in the
A)
Gaseous state
B)
Liquid state
C)
Solid state
D)
None of these
Metals are generally found in the solid state at ordinary conditions, and some can exist in the liquid state when heated above their melting points. In basic material science, a metal is not considered to exist in the gaseous state under normal conditions. Therefore, the correct option is (a) Gaseous state. Option (b) is possible for metals like mercury at higher temperatures or for melted metals, and option (c) is the most common natural state of metals.
__________ is generally done to improve machinability of steel.
A)
Tempering
B)
Annealing
C)
Normalising
D)
Cyaniding
Annealing is generally done to improve the machinability of steel. It softens the metal, reduces hardness, and relieves internal stresses, making cutting and shaping easier. Tempering mainly increases toughness after hardening, normalising refines grain structure, and cyaniding is a surface hardening process.
A process of joining similar metals by application of heat with or without application of pressure and addition of filler material is called
A)
Smithing
B)
Forging
C)
Pattern making
D)
Welding
Joining similar metals by applying heat, with or without pressure and filler material, is the definition of welding. Smithing and forging are metal shaping processes, while pattern making is related to foundry work, not joining metals.
The most rapid method of forming metal into desired shapes by plastic deformation in between rolls is
A)
Tempering
B)
Rolling
C)
Hardening
D)
None of these
The process of forming metal into desired shapes by plastic deformation between rolls is called rolling. In rolling, the metal is passed through rotating rolls that reduce thickness or change cross-section efficiently and rapidly. Tempering and hardening are heat-treatment processes, not shaping processes, so they are incorrect.
Which of the following statement is true?
A)
Worm gearing is widely used to transmit power at high velocity ratios between non-intersecting shafts that are usually, but not necessarily, at right angles
B)
Spur gearing is widely used to transmit power at high velocity ratios between non-intersecting shafts that are usually, but not necessarily, at right angles.
C)
Vee belt is widely used to transmit electrical power.
D)
None of these
Option (a) is correct: worm gears are used for high velocity ratio transmission between non-intersecting shafts, usually at right angles. Option (b) is incorrect because spur gears are used between parallel shafts, not non-intersecting shafts. Option (c) is incorrect because V-belts transmit mechanical power, not electrical power. Therefore, (a) is the true statement.
The device for smoothing out the power impulses from the engine is called
A)
Clutch
B)
Differential
C)
Flywheel
D)
Torque converter
A flywheel stores excess energy during the power stroke and releases it during the non-power strokes, thereby smoothing out fluctuations in engine power output. A clutch is for engaging/disengaging power transmission, a differential allows wheels to rotate at different speeds, and a torque converter transmits and multiplies torque in automatic transmissions.
Which transmission unit disengages the drive and provides a smooth take up the drive?
A)
Final drive
B)
Differential
C)
Clutch
D)
Gearbox
A clutch is the transmission unit used to engage and disengage the engine from the gearbox. It allows the driver to disconnect the drive momentarily and then take up the drive smoothly without shock. Final drive transmits power to the wheels, the differential allows different wheel speeds during turning, and the gearbox changes speed/torque ratios.
Power may be transmitted between parallel shafts by means of
A)
Worm gears
B)
Clutches
C)
Roller chains
D)
None of these
Power transmission between parallel shafts is commonly done by roller chains. Worm gears are used for non-parallel, typically right-angle shafts, and clutches are for engaging/disengaging power transmission, not for transmitting power between shafts as such. Hence, the correct answer is roller chains.
In forging operation of high speed steel, the operation should be carried out at
A)
900 to 1100°C
B)
1100 to 1300°C
C)
1300 to 1500°C
D)
None of these
High speed steel is forged at a comparatively lower temperature range than plain carbon steels because it loses hardness rapidly and may crack or overheat if heated too much. The usual forging temperature range for HSS is about 900 to 1100°C. Hence, option (a) is correct. Options (b) and (c) are too high for safe forging of HSS, and (d) is incorrect.
The maximum permissible variation in the size of the part is
A)
Basic dimensions
B)
Tolerance
C)
Clearance
D)
None of these
The maximum permissible variation in the size of a part from its basic size is called **tolerance**.
- **Basic dimension** is the intended or nominal size.
- **Clearance** is the intentional gap between two mating parts.
- Therefore, the correct term for allowable variation in size is **tolerance**.
A process of joining similar metal by rivet is called
A)
Welding
B)
Balancing
C)
Rivetting
D)
None of these
Joining similar metal plates or parts by using rivets is called rivetting. Welding joins metals by fusion, while balancing is unrelated to joining. Therefore, the correct option is (c) Rivetting.
Mark the one alternative that is nearest in meaning to the word - Nullity
A)
Impress
B)
No effect
C)
Seclude
D)
Astound
The word 'nullity' means something that is void, invalid, or without legal force; in general usage it can mean something of no value or no effect. Among the options, 'No effect' is the nearest in meaning. The other options—'Impress', 'Seclude', and 'Astound'—are unrelated to the meaning of nullity.
Which one is not included in major elements in Air conditioning?
A)
Compressor
B)
Condenser
C)
Evaporator
D)
None of these
In an air-conditioning system, the major elements of the refrigeration cycle include the compressor, condenser, and evaporator (along with the expansion device). Since all three options (a), (b), and (c) are major elements, none of them is excluded. Therefore, the correct answer is (d) None of these.
A dirty exhaust and intense diesel knock from a C.I. engine is caused by
A)
High Cylinder temperature
B)
Poor fuel atomization
C)
Supplying insufficient fuel to suit the air
D)
Breaking up the injected fuel into very fine particles
In a C.I. (diesel) engine, dirty exhaust and intense diesel knock usually occur when the injected fuel does not atomize properly. Poor atomization leads to larger fuel droplets, delayed and uneven combustion, incomplete burning, and thus smoky/dirty exhaust along with sharp pressure rise causing knock. High cylinder temperature is not the primary cause here, and supplying insufficient fuel to suit the air would generally reduce smoke rather than cause it. Breaking up fuel into very fine particles is desirable because it improves combustion, so it is the opposite of the cause.
An electrically operated device used to keep houses, offices and laboratories cool during summer and warm during winter, which not only controls temperature but also regulates humidity is
A)
Air circulator
B)
Air conditioner
C)
Air heater
D)
None of these
An air conditioner is an electrically operated device that controls both temperature and humidity, keeping indoor spaces cool in summer and warm in winter. An air circulator only moves air, and an air heater only provides heat, so they do not regulate both temperature and humidity like an air conditioner does.