MCQ ISE 2500 Midterm 3
The term encapsulation refers to which one of the following plastics shaping processes: (a) casting, (b) compression molding, (c) extrusion of hollow forms, (d) injection molding in which a metal insert is encased in the molded part, or (e) vacuum thermoforming using a positive mold?
a
Most externally threaded fasteners are produced by which one of the following processes: (a) cutting the threads, (b) milling the threads, (c) tapping, (d) thread rolling, or (e) turning the threads?
d
The chemical formula for polyisoprene in natural rubber is which of the following: (a) CH2, (b) C2H4, (c) C3H6, (d) C5H8, or (e) C8H8?
d
The function of the ejection system is which one of the following: (a) move polymer melt into the mold cavity, (b) open the mold halves after the cavity is filled, (c) remove the molded parts from the runner system after molding, or (d) separate the part from the cavity after molding?
d
The input/output relationship of a sensor is called which one of the following: (a) analog, (b) con- verter, (c) sensitivity, or (d) transfer function?
d
The parting line in injection molding is which one of the following: (a) the lines formed where polymer melt meets after flowing around a core in the mold, (b) the narrow gate sections where the parts are separated from the runner, (c) where the clamping unit is joined to the injection unit in the molding machine, or (d) where the two mold halves come together?
d
Which one of the following is closest to the tem- peratures used in plasma arc cutting: (a) 2750%C (5000%F), (b) 5500%C (10,000%F), (c) 8300%C (15,000%F), (d) 11,000%C (20,000%F), or (e) 16,500%C (30,000%F)?
d
Which one of the following processes would be appropriate for cutting a hole of 0.003 inch diame- ter through a plate of aluminum that is 1/16 in thick: (a) abrasive jet machining, (b) chemical mill- ing, (c) EDM, (d) laser beam machining, (e) oxy- fuel cutting, (f) water jet cutting, and (g) wire EDM?
d
A branched molecular structure is stronger in the solid state and more viscous in the molten state than a linear structure for the same polymer: (a) true or (b) false?
a
A molding operation that uses sheet-molding com- pound (SMC) is a form of which one of the follow- ing: (a) compression molding, (b) contact molding, (c) injection molding, (d) open mold processing, (e) pultrusion, or (f) transfer molding?
a
A positive mold with a smooth surface will produce a good finish on which surface of the laminated product in the hand lay-up method:(a) inside sur- face or (b) outside surface?
a
A stepper motor is which one of the following types of devices: (a) actuator, (b) interface device, (c) pulse counter, or (d) sensor?
a
Degree of polymerization is which one of the fol- lowing: (a) average number of mers in the molecule chain; (b) proportion of the monomer that has been polymerized; (c) sum of the molecule weights of the mers in the molecule; or (d) none of the above?
a
Filament winding involves the use of which one of the following fiber reinforcements: (a) continuous filaments, (b) fabrics, (c) mats, (d) prepregs, (e) short fibers, or (f) woven rovings?
a
In robotics, spray-painting applications are classi- fied as which of the following: (a) continuous path operation or (b) point-to-point operation?
a
Of the three polymer types, which one is the most important commercially: (a) thermoplastics, (b) thermosets, or (c) elastomers?
a
Polystyrene (without plasticizers) is amorphous, transparent, and brittle: (a) true or (b) false?
a
The basic difference between low-density poly- ethylene and high-density polyethylene is that the latter has a much higher degree of crystallinity: (a) true or (b) false?
a
The difference between industrial stitching and stapling is that the U-shaped fasteners are formed during the stitching process while in stapling the fasteners are preformed: (a) true or (b) false?
a
The fiber rayon used in textiles is based on which one of the following polymers: (a) cellulose, (b) nylon, (c) polyester, (d) polyethylene, or (e) polypropylene?
a
The standard coordinate system for numerical con- trol machine tools is based on which one of the following: (a) Cartesian coordinates, (b) cylindrical coordinates, or (c) polar coordinates?
a
The three basic types of automated systems used in manufacturing are fixed automation, programma- ble automation, and flexible automation. Flexible automation is an extension of programmable auto- mation in which there is virtually no lost produc- tion time for setup changes or reprogramming: (a) true or (b) false?
a
Ultrasonic machining can be used to machine both metallic and nonmetallic materials: (a) true or (b) false?
a
Water jet cutting is one of several ways of cutting or trimming uncured or cured FRPs; in the case of cured FRPs, the process is noted for its reduction of dust and noise: (a) true or (b) false?
a
Which of the following would tend to give higher material removal rates: (a) larger grain size, or (b) smaller grain size?
a
Which one of the following abrasive materials is most appropriate for grinding steel and cast iron: (a) aluminum oxide, (b) cubic boron nitride, (c) diamond, or (d) silicon carbide?
a
Which one of the following reinforcing geometries offers the greatest potential for strength and stiff- ness improvement in the resulting composite material: (a) fibers, (b) flakes, (c) particles, or (d) infiltrated phase?
a
Which one of the three polymer types does not involve cross-linking: (a) thermoplastics, (b) ther- mosets, or (c) elastomers?
a
A three-plate mold offers which of the following advantages when compared to a two-plate mold (two best answers): (a) automatic separation of parts from runners, (b) gating is usually at the base of the part to reduce weld lines, (c) sprue does not solidify, and (d) stronger molded parts?
a,b
Which of the following are reasons why mechanical assembly is often preferred over other forming processes (two best answers): (a) ease of assembly, (b) ease of disassembly, (c) economies of scale, (d) involves melting of the base parts, (e) no heat affected zone in the base parts, and (f) spe- cialization of labor?
a,b -Answer (e) might also be given, but it is not mentioned in the text.
Which of the following processes are associated with the production of plastic sheet and film (three correct answers): (a) blown-film extrusion process, (b) calendering, (c) chill-roll extrusion, (d) doctor blade method, (e) spinning, (f) thermoforming, and (g) transfer molding?
a,b,c
Which of the following polymers are normally thermoplastic (four best answers): (a) acrylics, (b) cellulose acetate, (c) nylon, (d) phenolics, (e) polychloroprene, (f) polyesters, (g) poly- ethylene, (h) polyisoprene, and (i) polyurethane?
a,b,c,g
Which of the following materials are used as fibers in fiber-reinforced plastics (four best answers): (a) aluminum oxide, (b) boron, (c) cast iron, (d) E-glass, (e) epoxy, (f) Kevlar 49, (g) polyester, and (h) silicon?
a,b,d,f
Which of the following will improve surface finish in grinding (three best answers): (a) denser wheel structure, (b) higher wheel speed, (c) higher work- speeds, (d) larger infeed, (e) lower infeed, (f) lower wheel speed, (g) lower workspeed, and (h) more open wheel structure?
a,b,g
Etch factor is equal to which of the following in chemical machining (more than one): (a) anisot- ropy, (b) CIt, (c) d/u, and (d) u/d; where C ¼ specific removal rate, d ¼ depth of cut, I ¼ current, t ¼ time, and u ¼ undercut?
a,c
The principal components of an injection molding machine are which two of the following: (a) clamp- ing unit, (b) hopper, (c) injection unit, (d) mold, and (e) part ejection unit?
a,c
Most rubber products are properly classified into which of the following categories (three best answers): (a) elastomer reinforced with carbon black, (b) fiber-reinforced composite, (c) parti- cle-reinforced composite, (d) polymer matrix com- posite, (e) pure elastomer, and (f) pure polymer?
a,c,d
Which of the following are sections of a conven- tional extruder barrel for thermoplastics (three best answers): (a) compression section, (b) die section, (c) feed section, (d) heating section, (e) metering section, and (f) shaping section?
a,c,e
Which of the following metals are used as the matrix material in fiber-reinforced MMCs (two best answers): (a) aluminum, (b) copper, (c) iron, (d) magnesium, and (e) zinc?
a,d
Which of the following processes are generally limited to thermoplastic polymers (two best answers): (a) blow molding, (b) compression mold- ing, (c) reaction injection molding, (d) thermo- forming, (e) transfer molding, and (f) wire coating?
a,d
Advantages of snap fit assembly include which of the following (three best answers): (a) components can be designed with features to facilitate part mating, (b) ease of disassembly, (c) no heat affected zone, (d) no special tools are required, (e) parts can be assembled quickly, and (f) stronger joint than with most other assembly methods?
a,d,e
Which of the following processes would be appli- cable to produce hulls for small boats (three best answers): (a) blow molding, (b) compression mold- ing, (c) injection molding, (d) rotational molding, and (e) vacuum thermoforming?
a,d,e
Which of the following will help to reduce the incidence of heat damage to the work surface in grinding (four correct answers): (a) frequent dress- ing or truing of the wheel, (b) higher infeeds, (c) higher wheel speeds, (d) higher workspeeds, (e) lower infeeds, (f) lower wheel speeds, and (g) lower workspeeds?
a,d,e,g
In which of the following properties do plastic parts often compare favorably with metals (two best answers): (a) impact resistance, (b) resistance to ultraviolet radiation, (c) stiffness, (d) strength, (e) strength-to-weight ratio, and (f) temperature resistance?
a,e
The APT command GORGTis which of the follow- ing (two best answers): (a) continuous path com- mand, (b) geometry statement involving a volume of revolution about a central axis, (c) name of the humanoid in the latest Star Wars movie, (d) point- to-point command, and (e) tool path command in which the tool must go right in the next move?
a,e
Which of the following are considered good product design rules for automated assembly (two best answers): (a) design the assembly with the fewest number of components possible, (b) design the product using bolts and nuts to allow for dis- assembly, (c) design with many different fastener types to maximize design flexibility, (d) design parts with asymmetric features to mate with other parts having corresponding (but reverse) features, and (e) limit the required directions of access when adding components to a base part?
a,e -All of the other answers go against design-for-assembly principles.
A SCARA robot is normally associated with which one of the following applications: (a) arc welding, (b) assembly, (c) inspection, (d) machine loading and unloading, or (e) resistance welding?
b
Among the thermosetting polymers, the most widely used commercially is which one of the fol- lowing: (a) epoxies, (b) phenolics, (c) silicones, or (d) urethanes?
b
Applications of electron beam machining are lim- ited to metallic work materials because of the need for the work to be electrically conductive: (a) true or (b) false?
b
As the temperature of a polymer increases, its density (a) increases, (b) decreases, or (c) remains fairly constant?
b
Of the following abrasive materials, which one has the highest hardness: (a) aluminum oxide, (b) cubic boron nitride, or (c) silicon carbide?
b
Pultrusion is most similar to which one of the following plastic shaping processes: (a) blow-mold- ing, (b) extrusion, (c) injection molding, or (d) thermoforming?
b
The reinforcing phase is the matrix within which the secondary phase is imbedded: (a) true or (b) false?
b
The term deep grinding refers to which one of the following: (a) alternative name for any creep feed grinding operation, (b) external cylindrical creep feed grinding, (c) grinding operation performed at the bottom of a hole, (d) surface grinding that uses a large crossfeed, or (e) surface grinding that uses a large infeed?
b
Use of a parison is associated with which one of the following plastic shaping processes: (a) bi-injection molding, (b) blow molding, (c) compression mold- ing, (d) pressure thermoforming, or (e) sandwich molding?
b
Which of the following plastics has the highest market share: (a) phenolics, (b) polyethylene, (c) polypropylene, (d) polystyrene, or (e) polyvinylchloride?
b
Which one of the following abrasive materials is most appropriate for grinding hardened tool steel: (a) aluminum oxide, (b) cubic boron nitride, (c) diamond, or (d) silicon carbide?
b
Which one of the following conventional machin- ing processes is closest to grinding: (a) drilling, (b) milling, (c) shaping, or (d) turning?
b
Which one of the following is the chemical formula for the repeating unit in polyethylene: (a) CH2, (b) C2H4, (c) C3H6, (d) C5H8, or (e) C8H8?
b
Machining is never used for rapid prototyping because it takes too long: (a) true or (b) false?
b -Desktop milling is the principal material removal technology used for rapid prototyping.
Chemical milling is used in which of the following applications (two best answers): (a) drilling holes with high depth-to-diameter ratio, (b) making in- tricate patterns in thin sheet metal, (c) removing material to make shallow pockets in metal, (d) removing metal from aircraft wing panels, and (e) cutting of plastic sheets?
c,d
The two most common polymer foams are which of the following: (a) polyacetal, (b) polyethylene, (c) polystyrene, (d) polyurethane, and (e) polyvinylchloride?
c,d
A programmable logic controller normally replaces which one of the following in control applications: (a) computer numerical control, (b) distributed process control, (c) humans, (d) industrial robots, or (e) relay control panel?
e
Of all of the current material addition rapid pro- totyping technologies, which one is the most widely used: (a) ballistic particle manufacturing, (b) fused deposition modeling, (c) selective laser sintering, (d) solid ground curing, and (e) stereolithography?
e
Of the following processes, which one is noted for the highest material removal rates: (a) electric discharge machining, (b) electrochemical machin- ing, (c) laser beam machining, (d) oxyfuel cutting, (e) plasma arc cutting, (f) ultrasonic machining, or (g) water jet cutting?
e
The leading commercial synthetic rubber is which one of the following: (a) butyl rubber, (b) isoprene rubber, (c) polybutadiene, (d) polyurethane, (e) styrene-butadiene rubber, or (f) thermoplastic elastomers?
e
Ceramic matrix composites are designed to over- come which of the following weaknesses of ceramics (two best answers): (a) compressive strength, (b) hardness, (c) hot hardness, (d) modulus of elasticity, (e) tensile strength, and (f) toughness?
e,f
A copolymer is a mixture of the macromolecules of two different homopolymers: (a) true or (b) false?
b
A thermoforming mold with a convex form is called which one of the following: (a) a die, (b) a negative mold, (c) a positive mold, or (d) a three-plate mold?
c
The forward movement of polymer melt in an extruder barrel is resisted by drag flow, which is caused by the resistance to flow through the die orifice: (a) true or (b) false?
b -Drag flow is the forward motion of the melt caused by the Archimedian screw principle in the barrel. The resistance to forward flow is called back pressure flow.
Rapid prototyping technologies are never used to make production parts: (a) true or (b) false?
b -Examples include small batch sizes of plastic parts that could not be economically injection molded, parts with intricate internal geometries, and one-of-a-kind parts such as bone replacements.
From the standpoint of assembly cost, it is more desirable to use many small threaded fasteners rather than few large ones to distribute the stresses more uniformly: (a) true or (b) false?
b -From the standpoint of assembly cost, it is more desirable to use few large threaded fasteners rather than many small ones because the large fasteners are easier to handle and since there are fewer of them, they require less assembly time.
The difference between a shrink fit and an expan- sion fit is that in a shrink fit the internal part is cooled to a sufficiently low temperature to reduce its size for assembly, whereas in an expansion fit, the external part is heated sufficiently to increase its size for assembly: (a) true or (b) false?
b -In a shrink fit the external part is heated and then cooled to shrink it onto the internal part. In an expansion fit, the internal part is cooled to contract it for assembly; it then expands to form the interference fit.
In rotational molding, centrifugal force is used to force the polymer melt against the surfaces of the mold cavity where solidification occurs: (a) true or (b) false?
b -It is the force of gravity in the doubly rotating mold that forces the polymer against the mold surfaces.
A contact input interface is a device that reads analog data into the computer from an external source: (a) true of (b) false?
b -The data is binary, not analog.
As the degree of crystallinity in a given polymer increases, the polymer becomes denser and stiffer, and its melting temperature decreases: (a) true or (b) false?
b -Melting temperature increases with higher degree of crystallinity.
Other names for open mold processes include which of the following (two best answers): (a) compression molding, (b) contact lamination, (c) contact mold- ing, (d) filament winding, (e) matched die molding, (f) preform molding, and (g) pultrusion?
b,c
Which of the following are characteristics of work situations that tend to promote the substitution of a robot in place of a human worker (three best answers): (a) frequent job changeovers, (b) hazard- ous work environment, (c) repetitive work cycle, (d) multiple work shifts, and (e) task requires mobility?
b,c,d
Identify which of the following applications are point-to-point and not continuous path operations (three correct answers): (a) arc welding, (b) drilling, (c) hole punching in sheet metal, (d) mill- ing, (e) spot welding, and (f) turning?
b,c,e
Anisotropic means which one of the following: (a) composite materials with composition consisting of more than two materials, (b) properties are the same in every direction, (c) properties vary depend- ing on the direction in which they are measured, or (d) strength and other properties are a function of curing temperature?
c
In filament winding, when the continuous filament is wound around the cylindrical mandrel at a helix angle close to 90!, it is called which of the following (one best answer): (a) bi-axial winding, (b) helical winding, (c) hoop winding, (d) perpendicular wind- ing, (e) polar winding, or (f) radial winding?
c
Smaller grain size in a grinding wheel tends to (a) degrade surface finish, (b) have no effect on surface finish, or (c) improve surface finish?
c
The ability of a positioning system to return to a previously defined location is measured by which one of the following terms: (a) accuracy, (b) control resolution, or (c) repeatability?
c
The arm-and-body of a robot manipulator gener- ally performs which one of the following functions in an application: (a) holds the end effector, (b) orients the end effector within the work volume, or (c) positions the wrist within the work volume?
c
Which one of the following RP technologies uses solid sheet stock as the starting material: (a) bal- listic particle manufacturing, (b) fused-deposition modeling, (c) laminated-object manufacturing, (d) solid ground curing, or (e) stereolithography?
c
Which one of the following is the most common poly- mer type in fiber-reinforced polymer composites: (a) elastomers, (b) thermoplastics, or (c) thermosets?
c
Which one of the following polymer types are most commonly used in polymer matrix com- posites: (a) elastomers, (b) thermoplastics, or (c) thermosets?
c
Which one of the following processes would be appropriate to drill a hole with a square cross section, 0.25 inch on a side and 1-inch deep in a steel workpiece: (a) abrasive jet machining, (b) chemical milling, (c) EDM, (d) laser beam machining, (e) oxyfuel cutting, (f) water jet cutting, or (g) wire EDM?
c
Which one of the three polymer types is not nor- mally considered to be a plastic: (a) thermoplastics, (b) thermosets, or (c) elastomers?
c
Wood is which one of the following composite types: (a) CMC, (b) MMC, or (c) PMC?
c
Which of the following are problems with the current material addition rapid prototyping tech- nologies (three best answers): (a) inability of the designer to design the part, (b) inability to convert a solid part into layers, (c) limited material variety, (d) part accuracy, (e) part shrinkage, and (f) poor machinability of the starting material?
c,d,e
Which of the following processes use mechanical energy as the principal energy source (three correct answers): (a) electrochemical grinding, (b) laser beam machining, (c) conventional milling, (d) ul- trasonic machining, (e) water jet cutting, and (f) wire EDM?
c,d,e
Hand lay-up is classified in which of the following general categories of PMC shaping processes (two best answers): (a) closed mold process, (b) com- pression molding, (c) contact molding, (d) filament winding, or (e) open mold process?
c,e
Which of the following RP technologies uses powders as the starting material (two correct answers): (a) ballistic particle manufacturing, (b) fused-deposi- tion modeling, (c) selective laser sintering, (d) solid ground curing, and (e) three-dimensional printing?
c,e
Which of the following metals are used as the matrix metals in nearly all WC cemented carbides and TiC cermets (two correct answers): (a) aluminum, (b) chromium, (c) cobalt, (d) lead, (e) nickel, (f) tungsten, and (g) tungsten carbide?
c,e
Which of the following methods and tools are used for applying the required torque to achieve a desired preload of a threaded fastener (three best answers): (a) arbor press, (b) preload method, (c) sense of feel by a human operator, (d) snap fit, (e) stall-motor wrenches, (f) torque wrench, and (g) use of lockwashers?
c,e,f
The three components of an automated system are which of the following: (a) actuators, (b) commu- nication system, (c) control system, (d) feedback loop, (e) humans, (f) power, (g) program of instruc- tions, and (h) sensors?
c,f,g
Which one of the following abrasive materials is most appropriate for grinding nonferrous metals: (a) aluminum oxide, (b) cubic boron nitride, (c) diamond, or (d) silicon carbide?
d
Which one of the following abrasive processes achieves the best surface finish: (a) centerless grind- ing, (b) honing, (c) lapping, or (d) superfinishing?
d
Which of the following rapid prototyping pro- cesses starts with a photosensitive liquid polymer to fabricate a component (two correct answers): (a) ballistic particle manufacturing, (b) fused- deposition modeling, (c) selective laser sintering, (d) solid ground curing, and (e) stereolithography?
d,e
Which of the following processes would be appro- priate for cutting a narrow slot, less than 0.015 inch wide, in a 3/8-in-thick sheet of fiber-reinforced plastic (two best answers): (a) abrasive jet machin- ing, (b) chemical milling, (c) EDM, (d) laser beam machining, (e) oxyfuel cutting, (f) water jet cutting, and (g) wire EDM?
d,f
Which of the following defects or problems is associated with injection molding (three correct answers): (a) bambooing, (b) die swell, (c) drag flow, (d) flash, (e) melt fracture, (f) short shots, or (g) sink marks?
d,f,g
In the Boeing 787 Dreamliner, what percentage of the aircraft consist of composite materials (two correct answers): (a) 12% by volume, (b) 20% by volume, (c) 50% by volume, (d) 80% by volume, (e) 12% by weight, (f) 20% by weight, (g) 50% by weight, and (h) 80% by weight?
d,g
Which of the following materials are not composites (two correct answers): (a) cemented carbide, (b) phenolic molding compound, (c) plywood, (d) Portland cement, (e) rubber in automobile tires, (f) wood, and (g) 1020 steel?
d,g
Which of the following are the common ways in which threaded fasteners fail during tightening (two best answers): (a) excessive compressive stresses on the head of the fastener because of force applied by the tightening tool, (b) excessive compressive stresses on the shank of the fastener, (c) excessive shear stresses on the shank of the fastener, (d) excessive tensile stresses on the head of the fastener because of force applied by the tightening tool, (e) excessive tensile stresses on the shank of the fastener, and (f) stripping of the internal or external threads?
e,f
Which of the following processes could be used to cut a large piece of 1/2-inch plate steel into two sections (two best answers): (a) abrasive jet machining, (b) chemical milling, (c) EDM, (d) laser beam machining, (e) oxyfuel cutting, (f) water jet cutting, and (g) wire EDM?
e,g