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The largest market share of MEMS products currently belongs to. microfluidics. microsensors. microaccelerometers.

MEMS components range in size from. 1 µm to 1 mm. 1 mm to 1 µm. 1 mm to 1 cm.

One nanometer is. 10^−6 m. 10^−9 m. 10^−12 m.

When we say a device is in mesoscale, we mean the device has a size in the range of. 1 µm to 1 mm. 1 mm to 1 µm. 1 mm to 1 cm.

The origin of microsystems can be traced back to the invention of. transistors. integrated circuits. silicon piezoresistors.

A modern integrated circuit may contain. 100,000 transistors and capacitors. 1,000,000 transistors and capacitors. 10,000,000 transistors and capacitors.

Miniaturization of computers was possible mainly because of. better storage systems. replacing vacuum tubes with transistors. the invention of integrated circuits.

In general, a microsystem consists of. one components. two components. three components.

The microsensor that is commonly used in air bag deployment systems in automobile is a. pressure sensor. inertia sensor. chemical sensor.

“Laboratory-on-a-chip” means. performing experiments on a chip. integration of microsensors and actuators on a chip. integration of microsystems and microelectronics on a chip.

The origin of modern microfabrication technology is. the invention of transistors. the invention of integrated circuits. the invention of micromachining.

The very first significant miniaturization occurred with. integrated circuits. laptop computers. mobile telephones.

The term micromachining first appeared in public in. the 1970s. the 1980s. the 1990s.

The term LIGA refers to. a process for micromanufacturing. a microfabrication process. a material treatment process.

A typical single ULSI chip may contain. one transistors. 10 transistors. 100 million transistors.

The development of integrated circuits began in. the 1960s. the 1970s. the 1950s.

The first digital computer, ENIAC, was developed in. the 1960s. the 1950s. the 1940s.

The aspect ratio of a microsystem component is defined as the ratio of. the dimensions in the height to those of the surface. the dimensions of the surface to those of the height. the dimensions in width to those of the length.

Market value of microsystems is intimately related to. volume demand. special features. performance of the products.

The most challenging issue facing microsystems technology is. the small size of the products. the lack of practical applications. its multidisciplinary nature.

The fundamental working principle of sensors is. to convert one form of energy to another form. to convert signals. to convert signs.

Acoustic sensors are used to detect. sound. temperature. chemical compositions.

Medical diagnosis uses. biosensors. biomedical sensors. both these sensors.

Biomedical sensors and biosensors are. the same thing. different things. neither of the above.

Biosensors require. biomolecules. electrochemical compounds. chemical compounds to work.

Chemical sensors work on the principle of. interaction of chemical and electrical properties of materials. chemical and biological interaction. mechanical and electrical interaction.

Any material that has a change of electrical properties after being exposed to particular gases can be used as a. chemical sensor. biosensor. thermal sensor.

Optical sensors work on the principle of. input heat generated by light. input photon energy by light. impact of electrons on solid surface.

Pressure sensors work on the principle of. deflecting a thin diaphragm. heating of a thin diaphragm. magnetizing a thin diaphragm by the pressurized medium.

The deflection of the thin diaphragm in micropressure sensors is measured by. mechanical means. optical means. electrical means.

Thermal sensors work on the principle of. thermal mechanics. thermometers. thermal electricity.

Thermopiles have. one junctions. two junctions. three junctions.

It takes a minimum of. one different materials to make thermal actuation work. two different materials to make thermal actuation work. three different materials to make thermal actuation work.

Shape memory alloys are materials that have. memory of their shape at the temperature of fabrication. programmed memory of their original shape. memory of their original properties.

Piezoelectric actuation works on the principle of. electric heating. mechanical-electrical conversion. electrical-mechanical conversion.

As the gap between the electrodes grows smaller, the electrostatic forces for actuation. grow stronger. grow weaker. do not change.

Electrostatic motors work on the principle of. closing gaps. alignment of opposing electrodes. both closing and alignment of opposing electrodes.

Microaccelerometers are used to measure. the velocity. the position. the dynamic forces associated with a rigid body moving at variable speed.

Microfluidics is used extensively in. thermomechanical analysis. biomedical analysis. electromechanical analysis.

A major problem in microchannel flow is. capillary effect. friction effect. pressure distribution.

Everything on our Earth is made from. 86 stable elements, and each element has a different atomic structure. 96 stable elements, and each element has a different atomic structure. 106 stable elements, and each element has a different atomic structure.

The core of an atom is a. neutron. nucleus. electron.

Elements have different properties because they have different. atomic structures. chemical compositions. physical compositions.

Elements that have similar properties when they have the same number of. electrons. protons. nuclei in the outer orbit of their respective atomic structures.

A nucleus contains. neutrons and protons. electrons and protons. neutrons and electrons.

Protons carry. positive charge. negative change. no charge.

Electrons carry. positive charge. negative charge. no charge.

Neutrons carry. positive charge. negative charge. no charge.

The outer orbit of atoms has a diameter that is. 100 times of that of a nucleus. 1000 times of that of a nucleus. 10,000 times of that of a nucleus.

A periodic table consists of. 96 elements. 103 elements. 108 elements.

Silicon atoms contain. 8 electrons. 10 electrons. 14 electrons.

Silicon atoms have. 4 electrons in their outer orbit. 6 electrons in their outer orbit. 8 electrons in their outer orbit.

An ion carries. electric charge. magnetic charge. electrostatic charge.

Ionization energy is the energy required to remove. neutrons from the outer orbit of an atom. protons from the outer orbit of an atom. electrons from the outer orbit of an atom.

The forces that bind the atoms in a molecule are called. intermolecular forces. electrostatic forces. interatomic forces.

Molecules are made of bounded. electrons. atoms. nuclei.

The intermolecular forces are. van der Waals in nature. electrostatic in nature. electromagnetic in nature.

The intermolecular forces, in general, are. proportional to the distances between molecules. equal to to the distances between molecules. inversely proportional to the distances between molecules.

The physical behavior of solid molecules is typically. strong in kinetic energy and atomic cohesive forces. weak in kinetic energy and atomic cohesive forces. weak in kinetic energy but strong in atomic cohesive forces.

Positive silicon can be produced by doping with. boron atoms. phosphorus atoms. either kind of atom.

Negative silicon can be produced by doping with. boron atoms. phosphorus atoms. either kind of atom.

Silicon is a semiconducting material. It can be made more electrically conductive by. doping process. a diffusion process. an electric implantation process.

N-type silicon is. less conductive as p-type silicon when doped with same dose of dopant. more conductive as p-type silicon when doped with same dose of dopant. about equally conductive as p-type silicon when doped with same dose of dopant.

Diffusion is a good way to. coat foreign materials in silicon substrates. implant foreign materials in silicon substrates. remove foreign materials in silicon substrates.

Diffusion analysis is based on. Fourier’s law. Fick’s law. Hooke’s law.

Plasma is a gas that. does carry electric charges. does not carry electric charges. may carry electric charges.

To maintain a plasma, one needs to keep supplying. high temperature to the plasma chamber. high pressure to the plasma chamber. high electrical field to the plasma chamber.

Electrochemistry involves. chemical reactions. ionization. decomposition of any substance caused by an electric current.

Electrolysis involves the production of. chemicals. chemical changes. ionization in a substance by the application of an electric potential.

Electrolysis uses. an ac power supply. a dc power supply. either an ac or dc power supply.

An electrolyte is. an electrode. the container. the solution that conducts electric current in an electrolysis process.

A cathode is the. positive electrode. negative electrode. neutral electrode.

Electrohydrodynamics deals with. dissolution of a fluid under an applied electric field. motion of a fluid under an applied electric field. solidification of a fluid under an applied electric field.

The principal use of electrohydrodynamics in microsystems is to. conduct electrolysis of minute chemicals. move minute amounts of fluid. detect minute amounts of fluid.

Electro-osmotic pumping is used to move minute amounts of. homogeneous fluid in capillary passages. heterogeneous fluid in capillary passages. any fluid in capillary passages.

Electropheretic pumping is used to move minute amounts of. homogeneous fluid in capillary passages. heterogeneous fluid in capillary passages. any fluid in capillary passages.

An anode is the. positive electrode. negative electrode. neutral electrode.

Quantum physics is used to describe. physical movement of atoms. energy transport. collisions of atoms in MEMS and nanosystems.

A quantum represents the smallest amount of. mass that any system can gain or lose. volume that any system can gain or lose. energy that any system can gain or lose.

Photons have the mass equal to. an electron. a neutron. zero.

In general, mechanical engineering principles derived for continua can be used for MEMS components with the size. larger than 1 nanometer. larger than 1 micrometer. larger than 1 picometer.

The theory of thin plate bending can be used to assess. the deflection only in thin diaphragms of micro pressure sensors. stresses only in thin diaphragms of micro pressure sensors. both the deflection and stresses in thin diaphragms of micro pressure sensors.

Square diaphragms are the. most popular geometry for micro pressure sensors. somewhat popular geometry for micro pressure sensors. least popular geometry for micro pressure sensors.

From a mechanics point of view, the most favored diaphragm geometry in micro pressure sensors is. circular. square. rectangular.

The principal theory used in microaccelerometer design is. plate bending. mechanical vibration. strength of materials.

The natural frequency of a microdevice is determined by its. mass. structure stiffness. mass and structure stiffness.

Microdevices in theory contain. one natural frequency. several natural frequencies. an infinite number of natural frequencies.

The analysis that attempts to determine several or all natural frequencies of a microdevice is called. modal. vibration. model analysis.

“Resonant” vibration of a device made of elastic materials occurs when the frequency of the excitation force. approaches any of the natural frequencies of the device. equals any of the natural frequencies of the device. exceeds any of the natural frequencies of the device.

The dashpot in a mass–spring vibration system serves the purpose of including the. damping effect on the system. acceleration effect on the system. deceleration effect on the system.

The damping effect in most microaccelerometer design is. very important. somewhat important. not important.

The damping effect by compressible fluids. increases with increase of the input frequency of the vibrating mass. decreases with increase of the input frequency of the vibrating mass. remains unchanged with increase of the input frequency of the vibrating mass.

The movement of the beam mass in force-balanced microaccelerometers is usually measured by. piezoresistor. piezoelectric. capacitance changes.

A vibrating beam will have its natural frequency. increased with increase of longitudinal stress in tension. decreased with increase of longitudinal stress in tension. unchanged with increase of longitudinal stress in tension.

Thermal stresses can be induced in mechanically constrained microdevice components by. uniform temperature rise. nonuniform temperature rise. any temperature rise.

Thermal stresses induced in a microdevice component made of dissimilar materials are due to. the difference of coefficients of thermal expansion of the materials. the weakness of the bonding interface. the degradation of materials after bonding.

Thermal stresses are induced in microdevices components free of mechanical constraints by. uniform temperature change. nonuniform temperature change. uniform temperature with time.

The creep deformation in a material becomes serious. at any temperature. above half the melting point. above half the homologous melting point.

The homologous melting point of a material is defined as the melting point on the scale of. absolute temperature. Celsius temperature. Fahrenheit temperature.

The parts of microsystems that are obviously vulnerable to creep failure are. solder bonds. epoxy resin bonds. silicone rubber bonds.

There are generally. two modes of fracture at the interfaces of microdevices. three modes of fracture at the interfaces of microdevices. four modes of fracture at the interfaces of microdevices.

The most frequently occurring fracture failure mode in microstructures is. Mode III. Mode II. Mode I.

Interfaces in microdevices are vulnerable to. mixed Mode I and II. mixed Mode I and III. mixed Mode II and III failure.

Fracture mechanics analysis of interfaces in microstructures requires the distribution of. normal stresses at the vicinity of the interface. shear stresses at the vicinity of the interface. both the normal and shear stresses at the vicinity of the interface.

The finite element method is a viable analytical tool for microstructures of. simple geometry. complex geometry and loading/boundary conditions. complex loading and boundary conditions.

The very first step in a finite element analysis is. to find the approximate solution. to set the governing equation and boundary condition. to subdivide the continuum into a number of subdivisions, a process called discretization.

The primary unknown quantity in a finite element analysis is the quantity that. appears in the formulation. the most important quantity. the most desirable quantity to be determined.

The primary unknown quantity in a stress analysis by the finite element method is. stress. strain. displacement.

The constitutive relation in a finite element analysis relates. the construction of appropriate formulations. the primary and other essential quantities. the loading and boundary conditions.

The von Mises stress represents. the stress component following the von Mises principle. the stress for a specific material. stresses in a structure of complex geometry.

The application of the scaling laws in miniaturization is to assess the consequences on. the physical effect on miniaturized products. the economic effect on miniaturized products. the market effect on miniaturized products.

Scaling laws are derived from. design engineers’ experience. the laws of physics. the market demands.

Scaling in geometry is critical in miniaturizing. moving components of MEMS products. sensing components of MEMS products. overall dimensions of MEMS products.

The Trimmer’s force scaling vector is used to assess miniaturization relating to. heat flow in solids in the design of MEMS. fluid flow in the design of MEMS. rigid-body dynamics in the design of MEMS.

For order 1 scaling such as surface-to-volume scaling, the acceleration varies. linearly. to the square power. to the cubic power.

The reason why electrostatic forces are favored over the electromagnetic forces in microactuation is that electrostatic forces scale. better than electromagnetic forces. worse than electromagnetic forces. about the same as electromagnetic forces.

Electromagnetic forces scale. 2 orders of magnitude worse than electrostatic forces. 3 orders of magnitude worse than electrostatic forces. 4 orders of magnitude worse than electrostatic forces.

The power loss due to electric resistivity is. much more severe in small-sized systems. less severe in small-sized systems. about the same in small-sized systems.

Pressure drop in a fluid flowing through a smaller circular conduit is. much greater than that in a larger conduit. about equal to that in a larger conduit. much less than that in a larger conduit.

The volumetric flow of fluid in a smaller circular conduit is. much greater than that in a larger conduit. about equal to that in a larger conduit. much smaller than that in a larger conduit.

The effect of surface tension on fluid flowing in a capillary tube makes the pressure drop. much greater than the same flow in mesosize tubes. about equal to the same flow in mesosize tubes. much less than the same flow in mesosize tubes.

The effect of surface tension on fluid flowing in a capillary tube makes the volumetric flow. much greater than the same flow in mesosize tubes. about equal to the same flow in mesosize tubes. much less than the same flow in mesosize tubes.

Heat flows. faster in a smaller solid than in a larger solid. slower in a smaller solid than in a larger solid. about the same in a smaller solid than in a larger solid.

The mode of heat transmission in gas in extremely narrow passages is. conduction. convection. radiation.

Heat transmission in gases is drastically different in a narrow passage of size less than. 5λ where λ is the mean free path of gas molecules. 7λ where λ is the mean free path of gas molecules. 9λ where λ is the mean free path of gas molecules.