1. NGÂN HÀNG CÂU HỎI 1.1.Câu hỏi loại 1

1. The four- stroke cycle

A 4-stroke cycle engine carried out four piston strokes during one combustion cycle - Intake Stroke, Compression Stroke, Power Stroke and Exhaust Stroke.

Induction stroke with the inlet valve open and the exhaust valve shut, the piston moves down the cylinder create a partial vacuum. This partial vacuum draws in the atomized fuel from the carburettor into the cylinder.

Intake stroke: The piston moves down the cylinder and the pressure will drop (negative pressure). The intake valve is open. Because of the low pressure the air/fuel mixture is sucked into the cylinder.

Compression stroke with both the inlet and exhaust valve closed, the piston moves up the cylinder, compressing the fuel mixture. Just before the end of the stroke, an electric spark across the points of the sparking plug ignites the petrol and air mixture.

Power stroke Both valves remain closed. During the tiny interval of time required for flame to establish itself, the piston has reached its highest position in the cylinder. The gas generated by the burning fuel now expands rapidly, driving the piston down the cylinder. This downward push is converted into a rotary movement by the connecting rod and crankshaft. A water jacket contained within the cylinder walls helps to conduct away the heat generated during this burning and thus keeps the engine cool.

Exhaust stroke The exhaust valve opens but the inlet valve remains shut. The piston moves up the cylinder, pushing the exhaust gas out through the exhaust valve. With the completion of the exhaust stroke the cycle begins again.

Questions:1. Why is it called a four-stroke cycle?(Because it carried out 4 piston strokes during one combustion

circle)2. Find a word in the passage that has the same meaning with “a flash of light”.( an electric spark)3. What happens to the mixture of air and fuel in Intake stroke?(The mixture of air and fuel is sucked into

the cylinder)4. In compression stroke when does the ignition start?(Before the end of the stroke)5. In power stroke what causes the piston to move down the cylinder?(The rapid expansion of the gas

generated by the burning fuel)6. What does the phrase “this downward push” refer to? (The moving of the piston downwards the

cylinder)7. There are three differences between Induction and Exhaust stroke. What are they?( The exhaust valve,

the inlet walve and the movement of the piston)8. When does the cycle begin again? (When the exhaust stroke completes)

2.

Consumption of energy resources, (e.g. turning on a light) is apparently harmless. However, producing that energy requires resources and contributes to air and water pollution. Many electric power plants burn coal oil or natural gas in order to generate electricity for energy needs. While burning these fossil fuels produces a readily available and instantaneous supply of electricity, it also generates air pollutants including carbon dioxide (CO2), sulfur dioxide and trioxide (SOx) and nitrogen oxides (NOx). Carbon dioxide is an important greenhouse gas which is thought to be responsible for some fraction of the rapid increase in global warming.

Burning fossil fuels for electricity generation also releases trace metals such as beryllium, cadmium, chromium, copper, manganese, mercury, nickel, and silver into the environment, which also act as pollutants. Certain renewable energy technologies do not pollute the environment in the same ways, and therefore can help contribute to a cleaner energy future for the world. Renewable energy technologies available for electricity production include biofuels, solar power, tidal power, wind turbines, hydroelectric power, etc. However, serious environmental concerns have been articulated by several environmental activists regarding these modes of electricity generation. According to them, some pollution is invariably produced during the manufacture and retirement of the materials associated with the machinery used in these technologies. A central way to avoid downsides of expanding energy production is energy conservation.

Questions:1.Does consumption of energy make the air and water polluted? ( Yes, it does)2.To generate electricity what are burned by many electric power plants? ( Coal oil and natural gas)3. What does burning fossil fuels generate? (It generates a readily available and instantaneous supply of

electricity)4.What are air pollutants?( They are carbon dioxide CO2, sulfur dioxide and trioxide SOX and nitrogen

oxides NOX)5. What does “it” (in line 5) refer to?( Burning fossil fuels)6.What trace metals that are released by burning fossil fuels?( Berrylium,cadmium, chromium, copper,

manganese, mercury, nickel and silver) 7.What do renewable energy technologies consist of?( biofuels, solar power, tidal power, wind turbines,

hydroelectric power,ect) 8.What are the disadvantages of using renewable energy technologies? ( The pollution and the retirement

of materials associated with the machinery used in these technologies)

3. Jet engines

Jet engines move the airplane forward with a great force that is produced by a tremendous thrust and causes the plane to fly very fast.

All jet engines, which are also called gas turbines, work on the same principle. The engine sucks air in at the front with a fan. A compressor raises the pressure of the air. The compressor is made up of fans with many blades and attached to a shaft. The blades compress the air. The compressed air is then sprayed with fuel and an electric spark lights the mixture. The burning gases expand and blast out through the nozzle, at the back of the engine. As the jets of gas shoot backward, the engine and the aircraft are thrust forward.

The image above shows how the air flows through the engine. The air goes through the core of the engine as well as around the core. This causes some of the air to be very hot and some to be cooler. The cooler air then mixes with the hot air at the engine exit area.

A jet engine operates on the application of Sir Isaac Newton's third law of physics: for every action there is an equal and opposite reaction. This is called thrust. This law is demonstrated in simple terms by releasing an inflated balloon and watching the escaping air propel the balloon in the opposite direction. In the basic turbojet engine, air enters the front intake and is compressed, then forced into combustion chambers where fuel is sprayed into it and the mixture is ignited.

Questions:

1. Why is a great force important to planes? (Because it causes the plane to fly very fast)2. What’s the other name of jet engines? ( It is “ gas turbines”)3. What is the compressor made up of? ( It is made up of fans with many blades)4. What does the word “this” refer to? ( The flowing of the air through and around the core)5. Where does the cooler air mix with the hot air? ( At the engine exit area)6. What is the principle for the operation of a jet engine? ( There is an equal and opposite reaction)7. What does the word “this law” refer to? ( Sir Isaac Newton’ third law of physics)8. In the basic turbojet engine, what happen to the air after it enters the front intake? ( It is compressed and

then forced into combustion chambers)4Today engines can produce enough power to lift the heaviest weights and drive the largest machines. The most powerful engine is the rocket engine; it can blast a spacecraft away from the pull of the Earth's gravity and out into space.

The engine that powers almost the world's cars is the internal-combustion engine. It uses the power of gases created by exploding fuel to produce movement. A mixture of air and tiny droplets of gasoline enters the engine's cylinders, each of which contains a piston. An electrical spark ignites the fuel mixture, producing gases which thrust each piston down.

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Many trains and trucks have been powered by diesel engine, which are internal-combustion engines that burn diesel fuel instead of gasoline. The engine works in the same way as a gasoline-fueled engine, but does not have spark plugs. Instead, each cylinder has an injector that squirts diesel fuel into the cylinder. The piston compresses the air, making it very hot. The hot air makes the diesel fuel explode.

If we use only gasoline and diesel engines today, there would be many problems with the environment. These kinds of engines produce waste gases that pollute the air and contribute to the greenhouse effect which causes the Earth's temperature to rise. Fortunately, electric motors, which are clean, quiet, and produce no pollution, have been used as an alternative. In fact, several car manufacturers are developing cars powered by electric motors. However, most electric cars are still experimental. If efficient batteries are successfully developed, electric cars will be an ideal solution for transportation.

Questions:1. Which engine is the most powerful? ( The rocket engine)2. What kind of engine powers almost all the world's cars? ( The internal combustion engine)3. Do diesel engines have spark plugs? ( No, they don’t)4. How does the diesel engine operate? ( It works in the same way as a gasoline-fueled engine)5. What does the phrase “these kinds of engines ” mean? ( It means “gasoline and diesel engines”)6. What happens if we use diesel engines today? ( They produce waste gases that pollute the air and

contribute to the greenhouse effect)7. What do several car manufacturers are doing? ( They are developing cars powered by electric motors)8. What is the name of the cars which are powered by electric motors? ( electric cars)

2.

1. The mechanical valve is one of the oldest pieces of technology known to mankind. If we define a valve as a device to regulate a flow, then the earliest recorded use of a valve was by Egyptian farmers in pre-Pyramid days to control the flow of Nile flood water in specially dug irrigation channels. The earliest valve was a simple piece of wood slotted down into a stream. Despite the engineering skills of the Romans, a similar device was still being used two thousand years later by Lancashire to cut off the mill stream or raceway, when repairs to the wheel were called for.

2. Whatever was happening on the open stream, it was within pipes that valves were developing. The Romans had piped water coming in from nearby stream to water towers above the city. Basic on/off valves regulated the flow into smaller distribution ducts and thence into private homes. Roman valves were cast in bronze and sealed with wood and animal hair against leaks, and some examples in museums show remarkable similarities to modern domestic taps!

3. The development of modern multi-position valves began in this country with the industrial revolution. The arrival of steam power and bulk material handling required more than simple on/off regulation of flow. With the development of rubber and rubber based materials, valves became more efficient, although 100% shut-off under pressure was still fairly uncommon.

Questions

1. What was the purpose of the earliest valve? ( It is a divice to regulate a flow)2. What do you know about the earliest valve? ( the earliest valve was a simple piece of wood slotted down

into a stream)3. Were Lancashire millers still using a valve of Roman design 2000 years after its invention? ( Yes, they

were.)4. What were Roman valves made of in order to avoid leaks? ( They were cast in bronze and sealed with

wood and animal hair against leaks)5. When did the development of modern multi-position valves begin? ( It began with the industrial

revolution)6. With what did valves become more efficient? ( With the development of rubber and rubber based

materials)7. What modern thing are Roman valves like? ( Domestic taps)8. Did valves achieve 100 percent of efficiency? ( No, they didn’t.)

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3. Zinc alloysZinc is the fourth most commonly used metal in the world. Much of it is in the form of zinc galvanizing used as a corrosion inhibitor for steels, but very large quantities of zinc alloys are used in casting and for bearing materials.High production quantities are made using zinc pressure die casting which results in very smooth surfaces and excellent dimensional accuracy. A variety of coating processes can be used to produce desirable finish appearance and to inhibit corrosion. Although the as-cast parts have inherently good corrosion resistance, the performance in some environment can be enhanced with chromate or phosphate treatments or anodizing. Painting and chrome plating are also used to produce a wide variety of attractive surface finishes.In addition to die casting, zinc products are often made by permanent mold casting, graphite permanent mold casting, and casting, and shell-mold casting. Other, less frequently used, processes are investment casting. Plaster-mold casting is often used for prototyping. Continuous casting is used to produce standard shapes (rod, bar, tube, and slabs). Prototypes or finished products can then be machined from these shapes.Zinc alloys typically contain aluminum and a small amount of magnesium. Some alloys include copper or nickel. The performance of the final products can be very sensitive to small amounts of other elements, and maximum limits are placed on the content of iron, lead, cadmium, and tin in some alloys. The most widely used zinc casting alloy is called alloy N0. 3, sometimes referred to as Zamak 3. It has 4% aluminum and 0.035% magnesium. Another is called Zamak 5, and it also contains 4% aluminum with 0.0055% magnesium and 1.0% copper. A group of alloys having higher aluminum content are the ZA-alloys, with ZA-8, ZA-12, and ZA-27 being the most popular. Questions:

1. What are zinc and zinc alloys used for? ( They are used for bearing materials)2. What does “it” in line 1 refer to? (It refers to “zinc”.)3. Why can a variety of coating processes be used? ( It can be used to produce desirable finish

appearance and to inhibit corrosion)4. How are zinc products made? ( They are often made by permanent mold casting, graphite permanent

mold casting, and casting and shell-mold casting.)5. What is the function of continuous casting? ( It is used to produce standard shapes such as rod, bar,

tube, and slabs)6. What do zinc alloys contain? (aluminum and a small amount of magnesium)7. What are the differences between Zamak 3 and Zamak 5? (Zamak 3 has more magnesium but it has no

copper.)8. What are the ZA-alloys? ( They are a group of alloys having higher aluminum content)

7. PlasticsPlastics include a wide variety of materials formed of large molecules called polymers. The thousands of different plastics are created by combining different chemicals to form long molecular chains. One method of classifying plastics is by the terms thermoplastic and thermosetting. In general, the thermoplastic materials can be formed repeatedly by heating or molding because their basic chemical structure is unchanged from its initial linear form. Thermosetting plastics do undergo some change during forming and result in a structure in which the molecules are cross-linked and form a network of interconnected molecules. Some designers recommend the terms linear and cross-linked in place of the more familiar thermoplastic and thermosetting.Selecting a plastic for a particular application is a complex process and usually involves compromises among properties related to strength, weight, toughness, ease of processing, appearance, life, and other properties. Designers should consult suppliers and should evaluate several candidate plastics before setting final specifications.The properties of plastics related to design performance and safety are similar to those of metals. Data sheets usually report tensile strength, modulus of elasticity in tension, hardness, impact strength, and strength and modulus in flexure. Other properties to be considered are density, friction coefficient, electrical resistively and dielectric constant, thermal expansion coefficient, water absorption, and appearance factors (color, clarity, weather resistance, and so on).A particular plastic is often selected for a combination of properties such as light weight, flexibility, color, strength, chemical resistance, low friction, or transparency. Table 2-8 lists the primary plastic materials used for

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six different types of applications. An extensive comparative study of the design properties of plastics can be found in References 12 and 19.Questions:

1. What are polymers? ( Polymers are plastics including a variety of materials formed of large molecules)

2. How are plastics created? (Plastics are created by combining different chemicals to form long molecular chains.)

3. What is the difference between thermoplastic and thermosetting? ( The basic chemical structure of thermoplastics is unchanged, thermosetting plastics undergo some change during forming)

4. Name the different terms used in the two methods of classifying plastics mentioned in the paragraphs. (linear and cross-linked )

5. Why should designers consult suppliers and evaluate several candidate plastics before setting final specifications? ( Because selecting a plastic for a particular application is a complex process and usually involves compromises among properties related to strength, weight, toughness, ease of processing, appearance, life, and other properties)

6. List the properties of plastics similar to those of metals. (tensile strength, modulus of elasticity in tension, hardness, impact strength, and strength and modulus in flexure)

7. How is a particular plastic often selected? (A particular plastic is often selected for a combination of properties such as light weight, flexibility, color, strength, chemical resistance, low friction, or transparency)

8. According to the text, where can the primary plastic materials used for six different types of applications be found? ( In table 2-8)

8.

The term stainless steel characterizes the high level of corrosion resistance offered by alloys in this group. To be classified as a stainless steel, the alloy must have a chromium content of at least 10%. Most have 12% to 18% chromium.The AISI designates most Stainless steels by its 200, 300 and 400 series. As mentioned previously, another designation system is the Unified Numbering System (UNS) developed by the SAE and the ASTM.The three main groups of stainless steel are austenitic, ferritic, and martensitic. Austenitic Stainless steels fall into the AISI 2000 and 300 series. They are general-purpose grades with moderate strength. Most are not heat-treatable, and their final properties are determined by the amount of working, with the resulting temper referred to as 1/4 hard, 1/2 hard, 3/4hard, and full hard. These alloys are nonmagnetic and are typically used in food processing equipment.Ferritic Stainless steels belong to the AISI 400 series, designated as 405, 409, 430, 446, and so on. They are magnetic and perform well at elevated temperatures, from 1300oF to 1900oF (700oC-1040oC), depending on the alloy. They are not heat- treatable, but they can be cold- worked to improve properties. Typical applications include heat exchanger tubing, petroleum refining equipment, automotive trim, furnace parts, and chemical equipment.Martensitic Stainless are also members of the AISI 400 series, including 403, 410, 414, 416, 420, 431, and 440 types. They are magnetic, can be heat-treated, and have higher strength than the 200 and 300 series, while retaining good toughness. Typical uses include turbine engine parts, cutlery, scissors, pump parts, valve parts, surgical instruments, aircraft fittings, and marine hardware.Questions1. What does the term Stainless steel characterize? (The term stainless steel characterizes the high level of corrosion resistance offered by alloys in this group )2. How to classify Stainless steel? (To be classified as a stainless steel, the alloy must have a chromium content of at least 10% )3. What are the names of most Stainless steels? (The AISI)4. How many groups of Stainless Steels? What are they? (There are three main groups of stainless steel. They are austenitic, ferritic, and martensitic)5. What does “they” (paragraph 2) refer to? (Austenitic Stainless steels )6. What do Ferritic Stainless Steels belong to? (They belong to the AISI 400 series)

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7. What are Ferritic Stainless steels used for? (They are used for heat exchanger tubing, petroleum refining equipment, automotive trim, furnace parts, and chemical equipment.)8. Do Martensitic Stainless Steels have high Strength? ( Yes, they do)

9.Straight Bevel Gears

The teeth of the straight bevel gear are straight and lie along an element of the conical surface. Lines along the face of the teeth through the pitch circle meet at the apex of the pitch cone. The centerlines of both the pinion and the gear also meet at this apex. In the standard configuration, the teeth are tapered toward the center of the cone.Key dimensions are specified either at the outer end of the teeth or at the mean, mid-face position. The relationships that control some of these dimensions are listed in table 8-7 for the case when the shafts are at the 900 angle. The pitch cone angles for the pinion and the gear are determined by the ratio of the number of teeth. Note that their sum is 900. Also, for a pair of bevel gears having a ratio of unity, each has a pitch cone angle of 450. Such gears, called miter gears, are used simply to change the direction of the shafts in a machine drive without affecting the speed of rotation.You should understand that many more features need to be specified before the gears can be produced. Furthermore, many successful, commercially available gears are made in some nonstandard form. For example, the addendum of the pinion is often made longer than that of the gear. Some manufactures modify the slope of the root of the teeth to produce a uniform depth, rather than using the standard, tapered form. The pressure angle, , is typically 200, but 22.50 and 250 are often used to avoid interference. The minimum number of teeth for straight bevel gears is typically 12.

Questions:1. Where are the teeth of a straight bevel gear? ( They lie along an element of the conical surface.)2. What affects the pitch cone angles for the pinion? (Lines along the face of the teeth through the pitch

circle meet at the apex of the pitch cone)3. What does the phase “such gears” refer to? (It refers to bevel gears having a ratio of unity)4. What is the function of miter gears? (They are used to change the direction of the shafts in a machine

drive without affecting the speed of rotation)5. What should manufactures notice before producing gears? ( They should understand that many more

features need to be specified before the gears can be produced)6. Give an example of a gear which is made in nonstandard form. (the addendum of the pinion)7. Why don’t manufactures often use the standard, tapered form? ( Because they modify the slope of the

root of the teeth to produce a uniform depth )8. What pressure angles are used frequently? (22.5 0 and 25 0

10. It is important to consider the design of the entire gear system when designing the gears because they must

work in harmony with the other elements in the system. Our discussion so far has been concerned primarily with the gear teeth, including the tooth form, pitch, face width, material selection and heat treatment. Also to be considered is the type of gear blank. are typically made in the plain style. Gears with pitch diameters of approximately 5.0 in through 8.0 in are frequently made with thinned webs between the rim and the Smaller gears and lightly loaded gears hub for lightening. Lager gears, typically with pitch diameters greater than 8.0 in, are made from cast blanks with spokes between the rim and the hub.

In many precision special machines and gear systems produced in large quantities, the gears are machined integral with the shaft carrying the gears. This, of course, eliminates some of the problems associated with mounting and location of the gears, but it may complicate the machining operations.

In general machine design, gears are usually mounted on separate shafts, with the torque transmitted from the shaft to the gear through a key. This setup provides a positive means of transmitting the torque while permitting easy assembly and disassembly. The axial location of the gear must be provided by another means, such as a shoulder on the shaft, a retaining ring, or a spacer.

Other considerations include the forces exerted on the shaft and the bearings that are due to the action of the gears. The housing design must provide adequate support for the bearings and protection of the interior components. Normally, it must also provide a means of lubricating the gears.

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Questions:1. Why should we consider the design of the entire gear system when designing the gears? ( Because they must work in harmony with the other elements in the system)2. Which gears are made in the plain style? (Smaller gears and lightly loaded gears)3. What are larger gears made from? (They are made from cast blanks with spokes between the rim and the hub)4. Where are the gears machined? (they are machined integral with the shaft carrying the gears )5. Where are grass mounted on separate shafts? (In general machine design)6. What are some examples of means providing the axial location of the gear? (a shoulder on the shaft, a retaining ring, and a spacer.)7. Why are the forces exerted on the shaft and bearings taken into account? (Because of the action of the gears)8. What does the word it in the last paragraph refer to? (The housing design)

11.In splash-type lubrication, one of the gears in a pair dips into an oil supply sump and carries the oil to the pitch line. At higher speeds, the oil may be thrown onto the inside surfaces of the case; then it flows down, in a controlled fashion, onto the pitch line. Simultaneously, the oil can be directed to the bearings that support the shafts. One difficulty with the splash type of lubrication is that the oil is churned; at high gear speeds, excessive heat can be generated, and foaming can occur.

A positive oil circulation system is used for high-speed and high-capacity systems. A separate pump draws the oil from the sump and delivers it at a controlled rate to the meshing teeth.

The primary functions of gear lubricants are to reduce friction at the mesh and to keep operating temperatures at acceptable levels. Heat is generated by the meshing gear teeth, by the bearings, and by the churning of the oil. This heat must be dissipated from the oil to the case or to some other external heat-exchange device in order to keep the oil itself below 160oF (approximately 70oC). Above this temperature, the lubricating ability of the oil, as indicated by its viscosity, is severely decreased. Also, chemical changes can be produced in the oil, decreasing its lubricity. Because of the wide variety of lubricants available and the many different conditions under which they must operate, it is recommended that suppliers of lubricants be consulted for proper selection.

1. When may the oil be thrown onto the inside surfaces? (At higher speeds)2. How is heat generated? (Heat is generated by the meshing gear teeth, by the bearings, and by the

churning of the oil)3. How can foaming occur? (at high gear speeds, excessive heat can be generated and foaming occur )4. What is used for high-speed systems? (A positive oil circulation system)5. What does the word it in the second paragraph refer to? (the oil)6. What are the advantages of gears lubricants? (the wide variety of lubricants available and the many

different conditions under which they must operate)7. What happens when the oil rises above 70 degrees centigrade? (the lubricating ability of the oil is

severely decreased )8. What does the text recommend? (suppliers of lubricants should be consulted for proper selection. )

12. Robot

There are many variations in definitions of what exactly is a robot. To try to provide a universally acceptable definition, the International Organization for Standardization gives a definition of robot in ISO 8373, which defines a robot as "an automatically controlled, reprogrammable, multipurpose, manipulator programmable in three or more axes, which may be either fixed in place or mobile for use in industrial automation applications". This definition is to be used when comparing the number of robots in each country.

In spite of the ISO definition, countries, such as the USA and Japan have different definitions of robots. Japan, for example, lists very many robots partly because more machines are counted as robots.

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Some simple robots are programmed to faithfully carry out specific actions over and over again without variation and with a high degree of accuracy. Industrial robots are much more flexible as to the orientation of the object on which they are operating or even the task that has to be performed on the object itself, which the robot may even need to identify.

Jobs which require speed, accuracy, reliability or endurance can be performed far better by a robot than a human. Hence many jobs in factories which were traditionally performed by people are now robotized. Robots have now been working in factories for more than fifty years, ever since the first Unimate robot was installed to automatically remove hot metal from a die casting machine. Today there are more than 1 million robots in operation worldwide (half of the robot population is located in Asia, 1/3 in Europe, and 16% in North America. Australasia and Africa each account for 1%...

Questions:1. What is ISO 8373? (It is the International Organization for Standardization)2. What does ISO 8373 define? (It defines a robot as "an automatically controlled, reprogrammable,

multipurpose, manipulator programmable in three or more axes, which may be either fixed in place or mobile for use in industrial automation applications")

3. Why is Japan’s definition different from ISO’s? (because in Japan, more machines are counted as robots.)3. How do simple robots work? (They are programmed to faithfully carry out specific actions over and

over again without variation and with a high degree of accuracy)4. How are industrial robots different from simple robots? (Industrial robots are much more flexible as to

the orientation of the object on which they are operating or even the task that has to be performed on the object itself, which the robot may even need to identify)

5. What kinds of jobs can a robot do better than a human? (Jobs which require speed, accuracy, reliability or endurance)

6. What did the first robot do? (It removed hot metal from a die casting machine automatically.)7. Which continent has the biggest robot population? ( Asia)

1.2.Câu hỏi loại 2 I.

helping both distribution either includingmechanics help cut distribute weightaccidents mechanisms appliances includes rotate

1. Mechanical engineering includes marine, automobile, aeronautical, heating and ventilating, and others.2. mechanisms make it possible to use escalator and lifts, travel in cars, and fly from continent to continent.3. Electrical engineering is about the generation and distribution of electricity and its many applications.4. weight is measured in Newtons but mass is measured in kilograms. 5. Rotary cams are used to rotate rotary motion into either reciprocating or oscillating motion.6. The moving piston makes the crankshaft rotate at great speed.7. A portable generator can produce a 700 watt output, enough to operate lights, televisions, and some

domestic appliances8. When the car is moving the slots ensure a flow of air over the brakes, helping to cool them down.9. The linear movement of a paper trimmer is used to cut the edge of the paper.10. Transformers are used on construction sites to step down the mains voltage to avoid accidents with hand

tools.

II.

engineering motors corrosion metal watercaliper engineers allow allows energymixture magnet pressure magnetized rotate

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1. Mechanical engineering are involved in support services such as roads, rail track, habours and bridges. 2. Mechanisms allows us to do simple things like switch on the light, turn taps, and open doors.3. Aluminium is a light metal which is used to make aircraft.4. The rotor is magnetized and as it spins round, electricity is generated in the stator windings through the

process of electro-magnetic induction.5. The valves close, the piston rises on the compression stroke and a spark within the upper chamber ignites

the mixture.6. When the driver presses the brake pedal, it pushes down the piston in the master cylinder, so creating

pressure in the fluid.7. When oil is used as a hydraulic fluid, it provides lubrication and reduces corrosion 8. The brake pads are held in a clamping device called a caliper9. As the car slow down, kinetic energy is converted to heat.10. Stepper motors are useful wherever accurate control of movement is required.

III.

carbon energy length down polesup steel oxides oxygen friction

another wheel products shape engineering

1. Cars, trains, ships, and planes are all products of mechanical engineering.2. Many mechanisms involve changing one kind of motion into another type.3. The way in which the follower moves and the distance it moves depends on the shape of the cam. 4. A portable generator works by turning the movement of a piston into electrical energy5. The friction is generated when the brakes-stationary pads mounted to the suspension system-rub against

metal disc turning with the wheels.6. The master cylinder has a smaller diameter than the wheel cylinder.7. The rotor in a stepper motor is constructed from several permanent magnets with north and south poles.8. A common example of corrosion is the rusting of steel where a conversion of metallic irons to a mixture

of oxides and other compounds occurs.9. High carbon steel contains more than 0.55% carbon10. Car wheels are ventilated to cool down the brake discs.

IV.electrical generated up away switcheddecrease open which demetallification down

high increase generate metal generate

1. Mining and medical engineering belong partly to mechanical and partly to electrical2. Rust may be dangerous to a structure because it decreases the cross-section of the metal.3. In the four stroke-cycle, the piston descends on the intake stroke, during which the inlet valve is open4. Although most electricity comes from power stations, power can also be generated by far smaller means.5. The armature windings is wound on the rotor which is fixed to the rotating crankshaft.6. Power is stepped up by a transformer to high voltages for long-distance distribution.7. Shut-off valve isolates the water column and air chamber from the turbine and generator when the plant is

switched off.8. When the footbrake pedal is released, the pressure in the hydraulic system falls and the pads move away from

the disc.9. demetallification . is the effective removal of one metal from an alloy, such as zinc from a copper-zinc alloy.10. A thermosetting plastic is a material which remains rigid at high temperature.

V.so decrease contains temperature corrosion

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fluid increase disc energy forcealign mild occurs drill because

1. Nylon is used for bearings because it is self-lubricating.2. Lasers can be used to measure and align structures.3. New bicycles have titanium gears to increase the speed of gear changes and decrease the chance of

slipping a gear.4. Microbiological corrosion is more often found in hot countries, but it also occurs in tanks, such as fuel

tanks.5. High carbon steel contains more than 0.55% carbon.6. disc brakes work by using friction and hydraulic power.7. When oil is used as a hydraulic fluid, it provides lubrication and reduces corrosion.8. Hard steel is harder and has greater tensile strength than mild steel.9. Refrigeration preserves food by lowering its temperature.10. In general, corrossion becomes worse when impurities are present in damp conditions.

VI. used zinc stepper metal engineers

immobile driving material soften immobilizessteel converted mechanic drives mechanical

1. Mining and medical engineering belong partly to mechanical and partly to electrical.2. Two branches of engineering include both electrical and mechanical engineers3. Brass is an alloy which consists of copper and zinc4. An insulator is a material which does not allow heat or current to slow easily.5. Thermoplastics soften when heated again and again.6. Polyester resin is used for boat and car bodies.7. The reciprocating motion of a piston is converted into a rotary motion by the crankshaft.8. A stepper motor does not run in the same way as a normal DC motor.9. Some cars are fitted with a security device which drives the engine.10. The gas expands, driving the piston down.

VII. generation elasticity bolted aerodynamic lengthenspositioned rotary low mechanisms longer

zinc moisture buoyancy distribution down

1. Gears involve rotary movement.2. Electrical engineering are concerned with the production and distribution of electricity to homes, offices, etc.3. The work volume of a manipulator is the volume of space into which it can be positioned4. After U the specimen lengthens but the load falls.5. Refrigeration preserves food by making its temperature low6. Impurities and moisture are two factors which encourage corrosion.7. Brass is an alloy which consists of copper and zinc8. New racing bicycles have aerodynamic handlebars since this reduces the rider’s wind resistance.9. In order to make the ship equilibrium the magnitudes of buoyancy and weight must be the same.10. mechanisms allow us to simple things like switch on lights, turn taps.

VIII.account rotational devise freedom devide

thermoplastics easily worth rotating innerin communicating up flexibility down

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1. Unlike thermosetting plastics, thermoplastics soften when heated again and again.2. It is worth point out that a human arm has much more freedom3. Stepper motor can be divided into two groups, one with permanent magnet and one without permanent magnet.4. Car wheels are ventilated to cool down the brake disc.5. It is imperative that a design takes into account whether a material will be affected and if corrosion is at what rate.6. The upper surface of a beam is in compression, but the inner surface is in tension.7. Lasers are ideal for. communicating in space.8. Post-type manipulator has one rotational and two linear. 9. A conductor is a material which allows heat or current to flow easily

IX.spoked reduce friction wheel either

electrical break release reduced resistanceimpurities electricity released resistant reduce

1. This generator is used because the turbine takes some time to build to a speed where it can generate electricity.2. Disc brakes work by using friction and hydraulic power3. The master cylinder has a smaller diameter than wheel cylinder4. Use as little force as possible to break down a machine into its components.5. In general, corrosion becomes worse when impurities are present in damp conditions6. Corrosion often occurs where water,spoked as a liquid or vapour in air of high humidity is present.7. When the push button is released the valve spring pushes up the spool.8. At intermediate substations, power is reduced to 11KV for light industry.9. Conventional racing bicycle use electrical wheels.10. New racing bicycles have aerodynamic handlebars as this reduces the rider’s wind resistanceX.

metal cylinder safety aerospace weightcube soft alloy compresses downmass caliper plane reciprocates safe

1. Car wheels are ventilated to cool down the brake disc.2. Thermoplastics can be made soft by heating them.3. Brass is a/an alloy which consists of copper and zinc.4. The piston in a combustion engine compresses.5. ABS is used for safety helmets.6. weight is measured in newtons.7. Components which fit on bicycle frames have benefited from aerospace engineering.8. The work volume of the Cartesian manipulator is a cube 9. The raising piston ………………the fuel mixture.10. The brake pads are held in a clamping device called a caliper

XI.generation generate direction make hindranceoscillating relatively forces energy space

spaces common commonest down oscillates

1. As the car slows... down..., kinetic energy is converted to heat.2. Work volume of a manipulator is the volume of . spaces. into which it can be positioned.3. A Wells turbine keeps the air turning in one.. direction.4. Friction is sometimes a help, but it is often a hindrance

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5. Steel rods are used to make concrete beams stronger.6. The pendulum of a clock oscillates , it means that the pendulum swings backwards and forwards.7. Buoyancy, elasticity, gravity and friction are important forces in engineering.8. Electricity generation is concerned with power station. 9. A relatively small force applied on the pedal produces a large force on the brake pads. 10. One of the common causes of failure in the long term is corrosion.

XII.

degrees main down friction freedommanipulator weakened stronger structure impurities

fraction states station generator lubrication

1. The spherical manipulator has two rotational and one linear degrees of freedom.2. Car wheels are ventilated to cool down the brake discs.3. In order to achieve flexibility of motion in 3 dimensional space, a robot manipulator need to be able to

move in at least three dimensions.4. Steel rods are used to make concrete beams stronger .5. Portable generator are made up of two main parts: an engine and an alternator.6. Degree of freedom which is usually the same as the number of axes.7. Engineers reduce friction by using very highly polished materials and by lubricating their surfaces with

oil and grease.8. The world’s first power station in the open sea is to be stationed off Dounreay in Scotland.9. Oil has better lubrication ability and increase viscosity which allow much higher loads to be achieved.10. Generally, corrosion becomes worse when impurities are present in damp conditions.

1.3. Câu hỏi loại 31. Nylon is self-lubricating, therefore it is used for bearings.

→ Nylon is used for bearings because it is self-lubricating.2. A conductor is a material. It allows heat or current to flow easily.

→ A conductor is a material which allows heat or current to flow easily3. Concrete beams have steel rods near the lower surface since concrete is weak in tension.

→ Concrete is weak in tension , therefore concrete beams have steel rods near the lower surface.4. The gas expands, driving the piston down.

→ As the gas expands, it drives the piston down.5. The piston moves down the cylinder. This creates a partical vacuum.

→ The piston moves down the cylinder, which creates a partical vacuum.6. The caliper system ensures that the disc is gripped on both sides.

→ The caliper system makes sure that the disc is gripped on both sides7. Steel rods are used to make concrete beams stronger.

→ Steel rods are used in order to make concrete beams stronger8. Carbon fibre frames make racing bicycles lighter and stronger.

→ Carbon fibre frames lighten and strengthen racing bicycles. 9. Thermoplastics can be made soft by heating them.

→ Thermoplastics can be softened by heating them..10. Some cars are fitted with a security device which immobilizes the engine.

→ Some cars are fitted with a security device which makes the engine immobile. 11. Tensile forces will make a beam longer.

→ Tensile forces will lengthen a beam.12. Most companies have installed computers to control their production line.

→ Most companies have controlled their production line to instal computers.3. Manufacturers seek to keep costs to a minimum and profits to a maximum.

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→ Manufacturers seek to minimize the costs and maximize the profits.4. Lack of lubrication gives rise to shearing in bolts.

→ Shearing in bolts rises due to the lack of lubrication. 5. Wear and tear in machinery is caused by friction.

→ Friction causes wear and tear in machinery6. Shearing in metal is due to repeated bending.

→ Repeated bending causes shearing in mental.7. Overloading a circuit results in blown fuses.

→ Blown fuses result from overloading a circuit.8. Excessive heat is brought about by overrunning an electric motor.

→ Overrunning an electric motor brings in excessive heat.9. Plastics can be softened and moulded into useful articles. They can be moulded into plates, car

components and medical aids→ Plastics can be softened and moulded into useful articles such as plates, car components and

medical aids…10. Copper is used for electric wiring because it is highly conductive.

→ Copper is highly conductive , therefore it is used for electric wiring.11. As the piston ascends, it forces the products of combustion out.

→The piston ascends, forcing the products of combuistion out.12. Mechanisms deliver the power to do work therefore they play a vital role in industry.

→ Mechanisms play a vital role in industry because they deliver the power to work.13. Friction is essential in brakes, it is a nuisance in an engine

→ Friction is a nuisance in an engine because it is essential in brakes.14. Apply a gradually increasing force to the balance.

→ A gradually increasing force should be applied to the balance.15. Unlike the conventional bicycle, the new bicycle has a carbon fibre frame.

→ The new bicycle is different from the conventional bicycle in that it has a carbon fibre frame.16. The alternator runs at a steady 3000 rpm. This generates around 700 watts.

→ The alternator runs at a steady 3000 rpm, generating around 700 watts.17. Lack of lubrication leads to bearing failure.

→ Bearing failure is resulted from lack of lubrication.18. Nylon is a hard, tough thermoplastic. Nylon is self-lubricating.

→ Nylon, which is a hard, tough thermoplastic , is selt-lubricating.19. These is a slight drop in load on Sunday between 8a.m to 9a.m → The load is slightly dropped on Sunday between 8a.m and 9a.m.20. The new bicycle is lighter than the old. → The old bicycle is not as light as the new.21. Electronic deals with communications and equipment. → Communications and equipment are the concern of electronic.22. The foot pump is a class two lever as the load is between the effort and the fulcrum.

→The load is between the effort and the fulcrum, making the foot pump a class two level.23. Mild steel is a metal. It contains iron and 0.15% to 0.3% carbon.

→ Mild steel is a metal which contains iron and 0.15% to 0.3% carbon 24. Thermoplastics can be softened by heating them.

→ Thermoplastics can be made soft by heating them.25. Old bicycles have spoked wheels whereas new ones have disc wheels.

→ Old bicycles have spoked wheels. In contrast, new ones have disc wheels.26. The Switch is on, but the lamp dose not light

→ Although the switch is on, the lamp does not light.27. Mechanisms deliver the power to do work. They play a vital role in industry.

→ Mechanisms play a vital role in industry because they deliver the power to work.28. ABS has high impact strength. It is used for safety helmets.

–› ABS, which is used for safety helmets has high impact strength.29. Place a block of wood on a flat surface.

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–› A block of wood is placed on a flat surface.30. Compressive forces will make a beam shorter.

–› Compressive forces will shorten a beam.31. Friction results in wear and tear in machinery.

–› Wear and tear in machinery is resulted from friction.32. The piston creates a vacuum. This draws in fuel from the carburettor.

–› The piston creates a vacuum, which draws in fuel from the carburettor.33. Even if the robot manipulator could align a screwdriver properly, it is still impossible to carry out the

necessary rotating action.–› Although the robot manipulator could align a screwdriver properly, it is still impossible to carry out

the necessary rotating action.34. Pull the block along so that it moves at a steady speed.

–› The block should be pulled along so that it moves at a steady speed.35. The crankshaft spins round. This turns the rotor at 3,000 rpm.

→ The crankshaft spins round, which turns the rotor at 3,000 rpm.36. Many companies may make their operation more rational by reducing the variety of products they make.

–› Many companies may rationalize their operation by reducing the variety of products they make.37. Overrunning an electric motor causes excessive heat.

→ Excessive heat is the result of overrunning an electric motor. 38. Loss of strength is caused by reduction in cross-section.

–› Reduction in cross-section causes loss of sthength.39. The number of female students in engineering technology rises sharply from 1989 to 1990.

–› There is a sharp rise in the number of female students in engineering technology from 1989 to 1990.40. Although mechanical wrist could get into any position, they could only approach objects from a single

angle.–› Even if mechanical wrist could get into any position, they could only approach objects from a single

angel.41. ABS has high impact strength, so it is used for safety helmets.

–› ABS is used for safety helmets because it has high impact strength.42. The light stays on even if the belt is closed.

→ Although the belt is closed, the light stays on.43. The load falls steadily on Sunday morning.

→ There is a steady fall in the load on Sunday morning.44. A thermoplastic is a material. It becomes plastic when heated.

→ A thermoplastic is a material which becomes plastic when heated.45. Excessive heat is results from overrunning an electric motor.

→ Overrunning an electric motor results in excessive heat.46. High carbon steel is a metal. It contains iron and 0.7% to 1.4% carbon.

→High carbon steel is a metal which contains iron and 0.7% to 1.4% carbon 47. The caliper system makes sure that the disc is gripped on both sides.

→ The caliper system ensures that the disc is gripped on both sides.48. Overloading a circuit gives rise to blown fuse.

→ Overloading a circuit makes blown fuse rise.49. Carbon steels are made tough by heating and quenching.

→ Carbon steels are toughened by heating and quenching..50. New racing bicycles have disc to reduce wind resistance.

→ New racing bicycles have disc wheel to make wind resistance decrease.51. The new bicycle is different from the conventional one in that the gears are made of titanium.

→ Unlike the conventional bicycle, the gears of the new bicycle are made of titanium. 52. Polyester resin is a thermosetting plastic used for casting. It is used for boat and car bodies.

→ Polyester resin is a thermosetting plastic used for casting, for example, boat and car bodies.53. Civil engineering deals with roads and bridges.

→ Civil engineering is concerned with roads and bridges.54. As the gas expands, it drives the piston down.

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→ The gas expands, driving the piston down.55. The load rises sharply between 5 p.m and 8 p.m on weekdays.

→ The load goes up sharply between 5 p.m and 8 p.m on weekdays 56. A reamer is a tool used to make a hole larger.

→ A reamer is a tool used for making a hole larger.57. Automobile engineering deals with cars and trucks.

→ Cars and trucks are the concern of automobile engineering.58. Shearing in bolts is the effect of overtightening.

→ Overtightening causes shearing in bolts.59. Reduction in cross-section gives rise to loss of strength.

→ Loss of strength is increased by the deduction in cross-section.60. Oil can be used to loosen tight bolts.

→ Oil can be used to make tight bolts loose.61. An alloy is a metal. It is formed by mixing other metals or elements.

→ An alloy is a metal which is formed by mixing other metals or elements 62. The armature of the alternator rotates. This induces a current in the stator windings.

→ The armature of the alternator rotates, which induces a current in the stator windings.63. The piston creates a vacuum. This draws in fuel from the carburetor.

→ The piston creates a vacuum, which draws in fuel from the carbureto.64. The alternator runs at a steady 3000 rpm. This generates around 700 watts.

→ The alternator runs at a steady 3000 rpm, which generates around 700 watts 65. A torque wrench is used to make cylinder head bolts tight.

→ A torque wrench is used to tighten cylinder head bolts.66. After thermosetting plastics become hard, they cannot be softened again.

→ After thermosetting plastics become hard, they can not be made soft again.67. Overloading a circuit leads to blown fuses.

→ Blown fuses are caused by overloading a circuit.68. There is a gradual decrease in load on Saturday between noon to 5 p.m.

→ The load is gradually decreased on Saturday between noon to 5 p.m.69. People widely use aluminum for structural and mechanical applications.

→ Aluminum is widely used for structural and mechanical applications.70. A micrometer is an instrument. It is used for measuring small distances precisely.

→ A micrometer is an instrument which is used for measuring small distances precisely

1.4.Câu hỏi loại 41. Mechanical engineering deals with the design and manufacture of tools and machines, (ENGINEER)2. Electrical engineers are concerned with the production and distribution of electricity to homes, offices,

industry, etc. (DISTRIBUTE)3. Copper is .highly conductive so it is used for electric wiring. (HIGH)4. Oil can be used to loosen tight bolts. (LOOSE)5. The gas expands, drivingthe piston down. (DRIVE)6. electrical engineering includes electricity generating, electrical installation, lighting, etc. (ELECTRIC)7. This prototype wave-power plant on the Scottish island of Islay was constructed by building a concrete

water column across a natural gully on the shoreline. (BUILD)8. The generator is a wound rotor induction motor, which acts as a generator when it is turning at speeds

greater than 1,500 rpm. (GREAT)9. The turbine is a Wells turbine which keeps turning in one direction even through the air flow is constantly

changing direction. (TURN / CONSTANT)10. This motor is used because the turbine takes some time to build up to a speed where it can generate

electricity (BUILD / ELECTRIC)11. Plans have been approved for the construction of a 1 MW scheme. (CONSTRUCT)12. The disc is fixed to the wheel hub and bearing assembly so that it can rotate freely(FREE)13. pressing the brake pedal places the hydraulic fluid under greater pressure. (PRESS)14. Friction between the pads and the disc slows rotation of the disc and the wheel. (ROTATE)

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15. Disc brakes work by using friction and hydraulic power. (USE)16. When the car is moving the slots ensure a flow of air over the brakes, helping to cool them down.(HELP)17. When the driver presses the brake pedal, it pushes down the piston in the master cylinder, so creates

pressure in the fluid. (DRIVE / CREATE)18. The master cylinder has a smaller diameter than the wheel cylinder. (SMALL)19. A relatively small force applied on the pedal produces a large force on the brake pads. (RELATIVE /

FORCE)20. Corrosion weakens structures (WEAK)21. New technology allows manufacturers to increase production (MANUFACTURE)22. A mixture of hydrocarbon gases can be separated into its constituents by cooling the mixture. (COOL)23. The piston moves down the cylinder, creating a partial vacuum. (CREATE)24. The generator is a wound rotor induction motor, which acts as a generator when it is turning at speeds

greater than 1,500 rpm. (GENERATE)25. Pumping fluid into the main cylinder gradually raises the jack. (GRADUAL)26. A torque wrench is used to tighten cylinder head bolts. (TIGHT)27. The piston ascends, forcing the products of combustion out. (FORCE)28. A portable generator can provide electricity to power lights and other appliances. (ELECTRIC)29. Carbon fibre frames lighten and strengthen racing bicycle. (LIGHT)30. Particles and salt in the water can cause wear and corrosion (CORRODE)31. A common example of corrosion is the rusting of steel where a conversion of metallic iron to a mixture of

oxide and other compounds occurs. (CONVERT)32. The hot plastic is forced through the die to form a continuous length of pipe. (LONG)33. In areas where the power supply fluctuates, for sensitive equipment a device to stabilize the voltage is

required. (DEVISE)34. Lasers beams can be used for drilling diamonds. (DRILL)35. The new bicycle is more aerodynamic than the old. (AERODYNAMIC)36. Bicycles use a chain and sprocket system to transmit rotary motion from the driver shaft to the

…………….. shaft because of its strength and because it will not slip. (DRIVE)37. When lasers were invented in 1960, some people thought they could be used as “death rays”? (INVENT)38. Steel rods are used to make concrete beams stronger (STRONG)39. The controlling computer is fitted with appropriate interfaces (CONTROL)40. Wheels, gears and rollers involve rotation movement (ROTATE).41. Compressive forces will shorten a beam (SHORT)42. This is due to the rapid production of a tough adherent film of oxide which protects the metal from further

attack so that corrosion halts (PRODUCE)43. Many industrial processes have electronic control system, it is still mechanisms that deliver the power to do

the work (INDUSTRY)44. For heavy-duty hydraulic or pneumatic machines this will be a compression (COMPRESS)45. The spherical manipulator which has two rotational and one linear degrees of freedom (SPHERE)46. The fluid is pumped from the reservoir though the one-way valve into the main cylinder (PUMP)47. In recent years, aircraft manufacturers such as Boeing have been experimenting with composite materials

like Chevel and Carbon fibres. (MANUFACTURE)48. Bicycle frame designers share many aims with aircraft engineers (DESIGN)49. There are four forces in engineering: gravity, elasticity, buoyancy and friction forces (ELASTIC)50. Many mechanisms involve changing one kind of motion into another type. (CHANGE).51. Rust is a conversion of ……………………. iron to a mixture of oxides and other compounds. (METAL)52. In areas where the power supply fluctuates, for sensitive equipment a device to stablize (STABLE) the

voltage is required.53. Nowadays, electricity generators can be small enough to hold in the hand. (GENERATION)54. The electrical current is fed to the output terminals or sockets. (ELECTRICITY)55. Copper is conductive and malleable. (CONDUCTOR)56. The load falls steadily in the early morning. (STEADY)57. After U the specimen lengthens further but the load falls. (LONG)58. Urea formaldehyde can be used as an electrical insulator (INSULATE).

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59. The pendulum of a clock oscillates (OSCILLATE).60. toughness is one of the properties of copper. (TOUGH)61. On weekdays the load rises sharply (SHARP).62. In order to achieve flexibility of motion within a three dimensive space, a robot manipulator requires at

least three degrees of freedom. (DIMENSION)63. overloading (overload) a circuit causes short circuits.(OVERLOAD)64. The friction is generated when the brakes rub against metal disc turning with the wheels. (GENERATION)65. Lasers can carry many more information channels than microwaves because of it high frequency .

( INFORM/ FREQUENT) 66. One of the most common causes of failure in the long term is corrosion. (COMMON)67. Most industrial robots have a much more limited work volume because they are bolted to the floor.

(INDUSTRY)68. Which alloys have the highest resistance to corrosion? (RESIST)69. .compressive forces will make a beam shorter? (COMPRESS)70. Carbon steels are made tough by hottening and quenching. (HOT)71. Corrosion is also any deterioration in physical properties. (PROPER)72. A relatively small force applied on the pedal produces a large force on the brake pads. (RELATIVE)73. In the arts, Pop concerts are often accompanied by laser displays. (ACCOMPANY)74. A major consideration in engineering design is maintenance (MAINTAIN)75. Corrosion becomes worse when impurities are present in damp condition. (PURE)76. An important design issue for the manipulator is its work volume which makes robots multifunctional

(MULTIFUNCTION)77. In order to achieve flexibility of motion, a robot manipulator needs to be able to move in at least three

dimensions. (FLEXIBLE)78. Which alloys have the highest resistance to corrosion? (HEIGHT)79. apperance of aluminum alloys’ corrosion in white and grey powder. (APPEAR)80. The controlling computer controls the various compressors, stepper motors, and solenoids, and receives

signals from the manipulator’s sensors. (VARY)81. There is a rapid increase in length for each increase in load. (LONG)82. Corrosion not only changes the appearance of the metal but also results in a decrease in its cross-section.

(APPEAR).83. Each movement of a piston pumps a small amount of fluid. (MOVE)84. The crankshaft extends directly to the alternator. (DIRECT)85. A portable generator can provide electricity to power lights and other appliances. (ELECTRIC)86. Degrees of freedom are the differential dimensions in which a robot manipulator can move.

(DIFFERENCE)

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