Preparation Manual

Domain VIII—Physics

Competency 025—The teacher understands the description of motion in one and two dimensions.

19. Vector quantities include which of the following? Select all that apply.

1. Force
2. Kinetic energy
3. Acceleration
4. Electric field

AnswerEnter to expand or collapse answer.Answer expanded

Options A, C and D are correct because vector quantities have both a magnitude and a direction and this is true of force, acceleration and electric field. Option B is incorrect because kinetic energy has a magnitude but not a direction, which means that it is a scalar quantity.

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Competency 027—The teacher understands the concepts of gravitational and electromagnetic forces in nature.

20. On the basis of Coulomb's law, which of the following is true about the electrostatic force that two charged objects X and Y exert on one another?

1. The force is directly proportional to the sum of the squares of the charges of the two objects.
2. The force is inversely proportional to the square of the distance between the two objects.
3. If the charges on objects X and Y are of the same sign, then the force on object X is in the same direction as the force on object Y.
4. If the charges on objects X and Y have opposite signs, then the force on object X is in the same direction as the force on object Y.

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because, according to Coulomb's law, the electrostatic force between two charges is inversely proportional to the square of the distance between the charges. Option A is incorrect because, according to Coulomb's law, the electrostatic force between two charges is directly proportional to the product of the two charges, not the sum of the squares of the charges. Options C and D are incorrect because, according to Newton's third law, the electrostatic forces that the charges exert on each other are always in opposite directions, regardless of the signs of the charges.

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Competency 028—The teacher understands applications of electricity and magnetism.

21. Two 6 Ωohm resistors are connected in parallel to an ideal 24 V source. What is the current through the voltage source?

1. 2 A
2. 4 A
3. 6 A
4. 8 A

AnswerEnter to expand or collapse answer.Answer expanded

Option D is correct because the two resistors connected in parallel combine to have a 3 Ωohm equivalent resistance, while the ideal voltage source has zero internal resistance. Thus, by Ohm's law, the current through the 24 V source is equal to (24/3) A, or 8 A. Option A is incorrect because it gives the result for two 6 Ωohm resistors connected in series, not parallel. Option B is incorrect because it gives the current through a single 6 Ωohm resistor. Option C is incorrect because it is just a statement of the resistor value expressed in amps instead of ohms.

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Competency 029—The teacher understands the conservation of energy and momentum.

22. In an isolated system, which of the following quantities are conserved? Select all that apply.

1. Velocity
2. Linear momentum
3. Angular momentum
4. Energy

AnswerEnter to expand or collapse answer.Answer expanded

Options B, C and D are correct because, in an isolated system, linear momentum, angular momentum and energy are conserved quantities. Option A is incorrect because velocity is not a conserved quantity.

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Competency 031—The teacher understands the characteristics and behavior of waves.

23. Which of the following is a consequence of refraction of light?

1. The formation of an image after light passes through a lens
2. The bending and spreading of light as it passes through a narrow slit
3. The pattern formed when light passes through two narrow, parallel slits
4. The focusing of light into a small area after reflecting from a curved mirror

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because the bending or refraction of light by the lens material results in the image formed by the lens. Option B is incorrect because it is diffraction, not refraction, that causes light to bend or spread when passing through a slit. Option C is incorrect because the pattern formed when light passes through two slits is due to interference, not refraction. Option D is incorrect because it refers to the focusing of light from a curved mirror as a result of reflection, not refraction.

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Competency 032—The teacher understands the fundamental concepts of quantum physics.

24. According to the Bohr model of the hydrogen atom, what happens when an electron makes a transition from a lower energy level to a higher level?

1. The nucleus loses kinetic energy.
2. A photon is absorbed by the atom.
3. A neutron decays into a proton, an electron, and a neutrino.
4. A positron makes a transition from the higher level to the lower level.

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because the Bohr model describes the hydrogen atom in terms of discrete stationary energy levels, and it is the transition of an electron from a lower energy level to a higher energy level that results from the absorption of a photon by the atom. Option A is incorrect because the kinetic energy of the nucleus is outside the scope of the Bohr model. Option C is incorrect because it describes neutron decay, which is outside the scope of the Bohr model. Option D is incorrect because hydrogen atoms do not contain positrons.

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Domain IX—Chemistry

Competency 033—The teacher understands the characteristics of matter and atomic structure.

25. Of the following species, which has the largest ionic radius?

1. Na⁺N A positive
2. Mg²⁺M G 2 positive
3. Al³⁺A L 3 positive
4. Cl^–Cl negative

AnswerEnter to expand or collapse answer.Answer expanded

Option D is correct because the additional electron in Cl^–Cl negative increases the electron-electron repulsion and therefore the ionic radius is larger than the atomic radius. Cl^–Cl negative has the same electron configuration as Ar. Options A, B and C are incorrect because Na⁺, Mg²⁺, and Al³⁺N A positive, M G 2 positive, and A L 3 positive have the same electron configuration as Ne. The attractive forces exerted by the nucleus on the remaining electrons cause contraction, so the ionic radii decrease in the following order: Na⁺ > Mg²⁺ > Al³⁺N A positive is greater than M G 2 positive is greater than A L 3 positive.

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Competency 035—The teacher understands the properties and characteristics of ionic and covalent bonds.

26. Which of the following best describes the molecular geometry of formaldehyde H₂COH sub 2 C O?

1. Tetrahedral
2. Trigonal planar
3. Trigonal pyramidal
4. T-shaped

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because formaldehyde has 3 bonding electron domains. According to the VSEPR model, the molecular geometry is trigonal planar. Option A is incorrect because molecules with 4 bonding electron domains have tetrahedral geometry. Option C is incorrect because molecules with 3 bonding electron domains and one nonbonding electron domain have trigonal pyramidal geometry. Option D is incorrect because molecules with 3 bonding electron domains and 2 nonbonding electron domains have T-shaped geometry.

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Competency 036—The teacher understands and interprets chemical equations and chemical reactions.

27. Which of the following is the balanced equation for the displacement reaction of aluminum with silver nitrate?

1. Al + AgNO₃ → AlNO₃ + AgAl plus AgNO sub 3 yields AlNO sub 3 plus Ag
2. Al + 3 AgNO₃ → Al(NO₃)₃ + 3 AgAl plus 3 AgNO sub 3 yields Al open paren NO sub 3 close paren sub 3 plus 3 Ag
3. Al + AgNO₃ → AlN + AgO₃Al plus AgNO sub 3 yields AlN plus AgO sub 3
4. Al + Ag₃N → AlN + 3 AgAl plus Ag sub 3 N yields AlN plus 3 Ag

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because the reaction of aluminum with silver nitrate forms Al(NO₃)₃Al(NO sub 3) sub 3 and Ag. The formula for silver nitrate is AgNO₃AgNO sub 3. The equation is balanced. Option A is incorrect because the formula for aluminum nitrate is not correctly represented. Option C is incorrect because the incorrect products are formed. Option D is incorrect because silver nitrate and aluminum nitrate are incorrectly represented.

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Competency 037—The teacher understands types and properties of solutions.

28. Of the following solutions, which has the highest electrical conductivity?

1. 1 M NaCl
2. 1 M HCH₃CO₂1 M HCH sub 3 CO sub 2
3. 1 M HCl
4. 1 M Na₂SO₄1 M Na sub 2 SO sub 4

AnswerEnter to expand or collapse answer.Answer expanded

Option D is correct because 1 M Na₂SO₄1 M Na sub 2 SO sub 4 dissociates to produce 3 moles per liter of ions. Option A is incorrect because 1 M NaCl dissociates to produce 2 moles per liter of ions. Option B is incorrect because HCH₃CO₂HCH sub 3 CO sub 2, a weak acid, only partly dissociates in aqueous solutions and is a weak electrolyte. Option C is incorrect because 1 M HCl, a strong acid, dissociates to produce 2 moles per liter of ions.

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Competency 038—The teacher understands energy transformations that occur in physical and chemical processes.

Use the table below to answer the question that follows.

Specific heat of ice	2.03 J/g·°C
Specific heat of water	4.18 J/g·°C
Heat of fusion of ice	334 J/g

29. Based on the data in the table above, what is the change in heat content of 100. g of water when it is cooled from 20.0°C to –20°Cnegative 20 degrees C?

1. –45,820 Jnegative 45,820 J
2. –12,420 Jnegative 12,420 J
3. +33,400 Jpositive 33,400 J
4. +45,820 Jpositive 45,820 J

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because the change in heat content of 100. g of water when it is cooled from 20°C to ice at –20°Cnegative 20 degrees C is the sum of the heat released by the cooling of the water, the freezing of the water, and the cooling of the ice. Option B is incorrect because it is the sum of the heat released by cooling of the water and ice but does not include the heat released during the freezing process. Option C is incorrect because it is the amount of energy required to melt ice at 0°C. Option D is incorrect because it is the change in heat content for the reverse process of warming ice at –20°Cnegative 20 degrees C to water at 20°C.

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Competency 039—The teacher understands nuclear fission, nuclear fusion and nuclear reactions.

Use the equation below to answer the question that follows.

C mass number 14 atomic number 6 yields N mass number 14 atomic number 7 plus e negative

30. The isotope carbon-14 decays according to the equation shown above. The transformation is an example of

1. alpha decay.
2. beta decay.
3. gamma decay.
4. x-ray emission.

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because beta-minus decay is the process in which a neutron is converted to a proton and an electron, a beta particle, is emitted. Option A is incorrect because alpha decay is the process in which a helium ion, an alpha particle, is emitted from the nucleus and a lighter nuclide is produced. Option C is incorrect because gamma decay is the process in which electromagnetic radiation with high frequency and high energy is emitted from atomic nuclei and is indicated by the Greek symbol gamma γ. Option D is incorrect because x-rays are electromagnetic radiation emitted by electrons.

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Competency 040—The teacher understands oxidation and reduction reactions.

Use the table below to answer the question that follows.

Reduction Half-Reaction	E° (V)
Ag+(aq) + e– → Ag(s)Ag positive open paren aq close paren plus e negative yields Ag open paren s close paren	+0.80positive 0.80
Cu2+(aq) + 2e– → Cu(s)Cu 2 positive open paren aq close paren plus e negative yields Cu open paren s close paren	+0.34positive 0.34
Fe2+(aq) + 2e– → Fe(s)Fe 2 positive open paren aq close paren plus e negative yields Fe open paren s close paren	–0.44negative 0.44
Zn2+(aq) + 2e– → Zn(s)Zn 2 positive open paren aq close paren plus e negative yields Zn open paren s close paren	–0.76negative 0.76

31. Based on the standard reduction potentials in the table above, which of the following reactions will occur spontaneously?

1. 2 Ag(s) + Fe²⁺(aq) → 2 Ag⁺(aq) + Fe(s)2 Ag open paren s close paren plus Fe 2 positive open paren aq close paren yields 2 Ag positive open paren aq close paren plus Fe open paren s close paren
2. Cu(s) + Fe²⁺(aq) → Cu²⁺(aq) + Fe(s)Cu open paren s close paren plus Fe 2 positive open paren aq close paren yields Cu 2 positive open paren aq close paren plus Fe open paren s close paren
3. Fe(s) + Zn²⁺(aq) → Fe²⁺(aq) + Zn(s)Fe open paren s close paren plus Zn 2 positive open paren aq close paren yields Fe 2 positive open paren aq close paren plus Zn open paren s close paren
4. Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)Zn open paren s close paren plus Cu 2 positive open paren aq close paren yields Zn 2 positive open paren aq close paren plus Cu open paren s close paren

AnswerEnter to expand or collapse answer.Answer expanded

Option D is correct because the net potential for the reaction is E° = [+0.34 V + (+0.76 V)] = +1.10 VE degrees equals open bracket positive 0.34 V plus open paren positive 0.76 V close paren close bracket equals positive 1.10 V. The sign of the standard reduction potential for the species that is oxidized, Zn, is reversed before summing the standard reduction potentials for the two half-reactions. A net potential that is positive indicates that the reaction is spontaneous. Option A is incorrect because the net potential for the reaction is –1.24 Vnegative 1.24 V. Option B is incorrect because the net potential for the reaction is –0.78 Vnegative 0.78 V. Option C is incorrect because the net potential for the reaction is –0.32 Vnegative 0.32 V.

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Domain X—Scientific Learning, Instruction and Assessment

Competency 042—The teacher understands research-based theoretical and practical knowledge about teaching science, how students learn science and the role of scientific inquiry in science instruction.

32. Which of the following is an example of inquiry-based science learning?

1. A group of students uses small carts to study whether kinetic energy is conserved when they collide.
2. A classroom of students watches a video on the similarities and distinctions between work and impulse.
3. A teacher gives a presentation on the role heating and work play in the conservation of energy.
4. A student conducts a literature search on the role of entropy in thermodynamic systems.

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because inquiry-based science involves students doing a hands-on experiment to answer a question. Option B is incorrect because videos can be helpful, but they are not elements of inquiry-based learning. Option C is incorrect because teacher presentations are important, but they are not an element of inquiry-based learning. Option D is incorrect because searching and reading literature can have value, but they are not an element of inquiry-based learning.

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Domain XI—The Engineering Method

Competency 044—The teacher has a working knowledge of engineering fundamentals.

Use the figure below to answer the question that follows.

The figure represents the cross-section of a hydraulic system with two chambers and a connecting region between them at the bottom. Each chamber has a piston. The piston on the left has a small diameter, and the piston on the right has a large diameter. Below the piston on the left is the label A sub 1, and below the piston on the right is the label A sub 2.

33. A technician designs a hydraulic system to raise heavy objects. The cross-sectional area of the smaller piston is A₁A sub 1 and the cross-sectional area A₂A sub 2 of the larger piston is 10 times that of the smaller piston. The system is filled with an incompressible fluid. If the mechanical advantage of the system is 10, how much force must be applied to lift a 200-kilogram mass and on which piston should the force be applied? (Assume that the gravitational acceleration is 10 meters per second squared.)

1. A force of 200 newtons must be applied to the larger piston.
2. A force of 200 newtons must be applied to the smaller piston.
3. A force of 20 newtons must be applied to the larger piston.
4. A force of 20 newtons must be applied to the smaller piston.

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because the hydraulic press is based on Pascal's law: in a fluid at rest in a closed container, a pressure change at one point is transmitted — without loss — to every other point in the fluid, and is also transmitted onto the walls of the container. That means pressure is the same on both pistons. Moreover, pressure is equal to the force divided by the area on which it acts.

Let m be the mass, g the gravitational acceleration, F₁F sub 1 the force on piston 1, F₂F sub 2 the force on piston 2, A₁A sub 1 the area of piston 1, A₂A sub 2 the area of piston 2, p1 = ^F₁/_A1p1 equals F sub 1 over A sub 1 the pressure on piston 1 and p2 = ^F₂/_A2p2 equals F sub 2 over A sub 2 the pressure on piston 2. Because the pressure is equal and it is given that A₂ = 10A₁A sub 2 equals 10A sub 1, we have:
^F₁/_A1 = ^F₂/_A2
^F₁/_A1 = ^F₂/_10A1
10F₁ = F₂line 1: F sub 1 over A sub 1 equals F sub 2 over A sub 2 line 2: F sub 1 over A sub 1 equals F sub 2 over 10A sub 1 line 3: 10F sub 1 equals F sub 2

The technician will act on piston 1 in order to exert less force. To lift a 200 kilogram mass with force F₁F sub 1, first calculate F₂F sub 2, then solve for F₁F sub 1.
F₂ = (200 kg)10 ^m/_s² = 2000 N.
F₁ = ^F₂/₁₀ = 200 Nline 1: F sub 2 equals open paren 200 kg close paren open paren 10 fraction m over s squared close paren equals 2000 N. line 2: F sub 1 equals F sub 2 over 10 equals 200 N.
Option A is incorrect because the force is right but the piston is wrong. Option C is incorrect because both the force and the piston are wrong. Option D is incorrect because the piston is right but the force is wrong.

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Use the closed electrical circuit below to answer the question that follows.

The shape is a horizontal rectangle with an additional vertical line connecting the top and bottom sides. On the left side is a circle with a plus sign and a minus sign inside, representing a generator, labeled 10 V. On the top, between the left side and the inside vertical line, is a zigzag, representing a resistor, labeled R sub 1, 10 Ω (ohm). On the inside vertical line is another resistor, labeled R sub 2, 20 Ω (ohm). To the right of this resister is a V, with a plus sign above it and a negative sign below it. On the right side is another resistor, labeled R sub 3, 20 Ω (ohm).

34. The closed electrical circuit shown consists of a generator and three resistors, R₁, R₂ and R₃R sub 1 R sub 2 and R sub 3. The electromotive force of the generator is 10 volts. Which of the following is the second resistor's voltage, V?

1. 3.33 V
2. 5.00 V
3. 6.67 V
4. 10.00 V

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because of Ohm's law, which relates the voltage (V), the current (I) and the resistance (R) according to the formula V = RIV equals RI.

First resolve the complexity of the circuit by finding the resistance for the parallel circuits using the formula:

1/R2 – 3	= 1/R2 + 1/R3
	= 1/20 + 1/20
	= 1/10 ohms

line 1: 1 over R sub 2 to 3 equals 1 over R sub 2 plus 1 over R sub 3 line 2: equals 1 over 20 plus 1 over 20 line 3: 1 over 10 ohms
Then find the resistance of the circuit by adding R₁ and R_{2 – 3}, 20 + 10 = 30 ohmsR sub 1 and R sub 2 to 3, 20 plus 10 equals 30 ohms. Using Ohm's law and the fact that EMF of the generator equals the voltage of the circuit, I = ^V/_R = ¹⁰/₃₀ = ¹/₃I equals V over R equals 10 over 30 equals 1 over 3.

Further, as the current passes through this circuit it splits in half when it passes through the parallel circuits. This is because the resistance and voltage values are equal.

Applying Ohm's Law a second time:
V₂ = R₂I₂ = 20 ¹/₂ ¹/₃ ≈ 3.33 VV sub 2 equals R sub 2 I sub 2 equals 20 open paren 1 half close paren open paren 1 third close paren is approximately 3.33 V.
Options B, C and D are incorrect because the values of the voltages are wrong.

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35. A broken down car, with mass 1859 kilograms, is accelerated southward at 1.32 meters per second squared when pulled by a tow truck. Which of the following is closest to the force of friction if the tow truck exerts 2.84 kilonewtons, southward on the car?

1. 0.386 kilonewtons
2. 0.842 kilonewtons
3. 5.293 kilonewtons
4. 2840 kilonewtons

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because Newton's second law of motion states that the sum of the forces, F, on an object is equal to the total mass, m, of that object multiplied by the acceleration, a, that force gives to the object: F = maF equals ma.

The total force applied to the car is its mass, 1859 kilograms, times its acceleration, 1.32 meters per second squared:

F	= (1859)(1.32) = 2453.88 newtons
	= 2.45 kilonewtons

line 1: F equals open paren 1859 close paren open paren 1.32 close paren equals 2453.88 newtons line 2: equals 2.45 kilonewtons
In the system there are two forces: the tow truck force, F_tF sub t, and the friction, F_fF sub f.
F = F_t + F_fF equals F sub t plus F sub f, then F_f = F − F_t = 2.454 − 2.840 = –0.386 kNF sub f equals F minus F sub t equals 2.454 minus 2.840 equals negative 0.386 kN

The minus sign indicates that the friction forces are in the opposite direction of the motion and the direction of the total force.

Option B is incorrect because the correct value of F_fF sub f is 0.386 kN.

Option C is incorrect because 5.293 kN is the result of the algebraic sum of F_fF sub f and F, but F_f = F − F_tF sub f equals F minus F sub t.

Option D is incorrect because the correct value of friction F_fF sub f is 0.386 kN. Furthermore the friction must be lower than the tow truck force to have the car moving. With a friction of 2840 kN the car cannot move.

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Competency 046—The teacher understands basic principles of information technology and computers and the role of information technology.

36. A wireless communication system has been set up between two locations and is said to be problematic because it is band-limited. Which of the following is the most likely cause of the problem?

1. It takes too long to encode the bits that are to be transmitted
2. There is not enough computer memory in the system
3. There is not enough dedicated transmission bandwidth to send the information quickly enough
4. There are types of transmissions that are forbidden due to security risks

AnswerEnter to expand or collapse answer.Answer expanded

Option C is correct because "band-limited" is a common term meaning that there is not enough transmission frequency space to quickly and efficiently send information. Option A is incorrect because the time necessary for the transmission of data does not have a threshold that once exceeded may be considered a problem by the system. Option B is incorrect because a "band-limited problem" is not correlated to a computer memory problem. Option D is incorrect. When there are types of transmissions that are forbidden due to security risks, it's the firewall system or the security program that stops the transmission.

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Domain XII—The Engineering Profession

Competency 050—The teacher understands the concept of teaming, demonstrates knowledge of careers in engineering and understands the legal and ethical requirements of the engineering profession.

Use the table below to answer the question that follows.

Maximum repayment period	60 months
Maximum monthly payment	$20,000
Maximum total repayment	$1,000,000

37. The board of directors of a small engineering firm has approved a long-term investment in one of their projects that will require securing a $500,000 loan. The guidelines for the loan are listed in the table shown. Which of the following options represents an offer from a commercial banking institution that meets the criteria set by the board?

1. 48 months, at 12% annual interest, compounded quarterly
2. 30 months, at 24% annual interest, compounded quarterly
3. 36 months, at 3% simple and 36% annual interest
4. 24 months, at 4% simple and 48% annual interest

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because the use of the compound interest formula
A = P 1 + ^r/_n^ntA equals P open parent 1 plus r over n close paren to the power of n t, where P is the loan amount, $500,000500,000 dollars, t is the maximum repayment period of 4 years, r is the annual interest rate of 12% or 0.12, and n is 4 because the interest is compounded quarterly.

The total repayment is

A	= 500,0001 + 0.12/44(4)
	= 500,000(1.03)16
	= 802,353.22

Line 1: A equals 500,000 open paren 1 plus 0.12 over 4 close paren to the power of 4 open paren 4 close paren Line 2: equals 500,000 open paren 1.03 close paren to the power of 16 Line 3: equals 802,353.22
Comparing restrictions, option A's repayment period is under 60 months. Further, the monthly payment is ^802,353.22/₄₈ = 16,715.69802,353.22 over 48 equals 16,715.69, which is under the maximum monthly payment of $20,00020,000 dollars. Finally, the engineering firm will have to pay $802,353.22 over the course of the 48 months, which is less than maximum total repayment of $1,000,000.
Option B is incorrect because it does not meet the second restriction — maximum monthly payment — set by the board. Using the compound interest formula, the monthly payment would be ^895,423.85/₃₀ = $29,847.46895,423.85 over 30 equals 29,847.46 dollars, which is more than $20,00020,000 dollars per month. Option C is incorrect because it does not meet either the second or third restriction. To find the total repayment, use both the simple interest and simple annual interest formulas:
I _simple = Pi
A _simple = P(1 + tr)
Total = A _simple + I _simpleLine 1: I sub simple equals P times i Line 2: A sub simple equals P open paren 1 plus t times r close paren Line 3: Total equals A sub simple plus I sub simple.

Total	= A simple + I simple
	= 500,000(1 + (3)(0.36)) + 500,000(0.03)
	= 1,055,000

Line 4: Total equals A sub simple plus I sub simple Line 5: equals 500,000 open paren 1 plus 3 times 0.36 close paren plus 500,000 times 0.03 Line 6: equals 1,055,000
and the monthly payment is ^1,055,000/₃₆ = 29,305.601,055,000 over 36 equals 29,305.60.
Option D is incorrect because it does not meet the second restriction set by the board. The total is given by:

Total	= A simple + I simple
	= 500,000(1 + (2)(0.48)) + 500,000(0.04)
	= 1,000,000

Line 1: Total equals A sub simple plus I sub simple Line 2: equals 500,000 open paren 1 plus 2 times 0.48 close paren plus 500,000 times 0.04 Line 3: equals 1,000,000
The monthly payment would be: ^1,000,000/₂₄ = 41,666.671,000,000 over 24 equals 41,666.67.

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38. An engineering manager who supervises a team of twelve people has been assigned to generate reports from all four sectors of production. The manager is newly appointed and has been asked by the boss to practice delegation. Which of the following actions are most appropriate and efficient to get the reports completed?

1. Personally writing all the reports
2. Meet with senior members of the team to determine which team members are best suited to write the reports, and then let the senior members assign the reports to whoever is appropriate. The new manager will review and edit the reports before sending to the boss.
3. Assigning one report to each of the twelve team members and then personally reviewing, consolidating and rewriting all the reports to correct any important omissions
4. Assigning all four reports to one randomly selected team member, assuming that all members are well qualified to write a report

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because in order to practice delegation, the manager should share responsibilities. The most efficient way for the new manager to have the reports generated and to practice delegation is to meet with senior members of the team who know about the other employees' skills and then let senior members of the team assign the report writing to the most qualified individuals. It is a good practice for a manager to review and edit any report being sent to senior management. Option A is incorrect because the new manager does not delegate anything or share responsibilities in this process. Option C is incorrect because this solution is inefficient. Assigning one report to each of the twelve team members without regard to experience or ability may lead to omissions or may require additional time for completion. Further, by reviewing, consolidating, and editing each report, the manager may spend time that could be better allocated to other tasks. Option D is incorrect because the process is inefficient. Randomly assigning the report to one team member without regard to experience, ability or workload may lead to omissions, errors and an incomplete report.

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39. An engineering firm has been hired by the city to construct a bridge over a newly formed irrigation channel. The main professional engineer (PE) is out on medical leave, and another engineer has taken his place as temporary PE. The temporary PE has just been recently certified in Civil Transportation by the National Council of Examiners for Engineering and Surveying (NCEES) and he is competent but unsure of himself in certain areas of the safety requirements for the bridge. He would prefer to delay signoff until the experienced PE comes back, but an official from the city asks the temporary PE if it is possible to speed up the sign-off process. By signing off without having the experienced PE review the plan, this NCEES-licensed PE will be violating his obligation to which of the following?

1. To society
2. To society, his employer and his clients
3. To other licensees
4. To society, his employer, his clients and other licensees

AnswerEnter to expand or collapse answer.Answer expanded

Option D is correct because by certifying work in an area where the engineer is unsure of himself, he is putting society at risk, putting the reputation of his employer at risk, putting his clients at risk and by violating the professional code of ethics is putting the profession at risk. Therefore he is violating his obligation to all four entities mentioned in the answer choices. Options A, B and C are incorrect because they are not complete answers. Option D is the only complete answer that includes all groups affected by the engineer's choice.

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40. A chemical engineering company, ChemA, has developed a new type of chemical process and has patented a new piece of equipment to run the process. An engineer owns a small business that provides expendable parts and supplies for use with the equipment. According to the code of ethics, when asked at a press conference to give his opinion on the effectiveness of the new equipment over equipment using older techniques, the engineer should

1. refrain from making any comments since he has the potential to profit from the acceptance of the new equipment by the users.
2. make statements that are only highly technical in nature in order to confuse the press.
3. disclose his relationship with the company that manufactures the processing equipment before commenting or giving an opinion.
4. read a statement that has been prepared by ChemA specifically for the purposes of responding to questions from the press.

AnswerEnter to expand or collapse answer.Answer expanded

Option C is correct according to the code of ethics of the National Society of Professional Engineers. Option A is incorrect because according to the code of ethics of the National Society of Professional Engineers, honesty and information sharing must supersede profit. Option B is incorrect because according to the code of ethics of the National Society of Professional Engineers, everyone must encourage honesty and information sharing. It is ethically wrong for an engineer to intentionally confuse the press or the public. Option D is incorrect because reading a statement that has been prepared by ChemA instead of giving a personal opinion could indicate that he is withholding his real opinion in favor of ChemA and personal profit.

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Competency 051—The teacher knows how to provide a safe and productive learning environment.

41. A good lab instructor promotes a policy of safety awareness and helps students, faculty and staff develop positive attitudes toward safety. Which of the following is the best procedure to follow to help students prevent accidents in the lab?

1. Fully explaining all safety considerations to students at the beginning of each lab
2. Demonstrating safety procedures and identifying potential hazards before students begin their work and identifying hazards and applying safety procedures as appropriate throughout the lab
3. Posting and distributing written directions or warnings, when appropriate, about the safe handling of materials and equipment used in instruction
4. Regularly administering safety quizzes to students to ensure that safe procedures are followed

AnswerEnter to expand or collapse answer.Answer expanded

Option B is correct because it is the best way to prevent accidents. Practical activity stimulates interest and attention. Safety procedures are more easily learned if developed practically rather than theoretically. Identifying potential hazards and demonstrating the corresponding safety procedures will allow everyone to act properly under dangerous conditions. As safety hazards arise, they must be addressed immediately. Option A is in correct because while fully explaining applicable safety considerations is a good practice, the process described in option B is more effective if the instructor wants to raise safety awareness for each practical activity. Options C and D are incorrect because written materials and quizzes can help reinforce safety procedures, but they may not address practical daily activities.

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42. A group of students are participating in a lab activity in which they design and test different types of electrical circuits. Which of the following safety procedures is most important for the students to follow?

1. Removing drinks from the laboratory area prior to the activity
2. Wearing safety goggles and aprons while in the lab area
3. Disposing of chewing gum before starting the lab activity
4. Keeping loose hair and clothing tied back during the lab activity

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because water and other liquids can conduct electricity. Removing drinks from the lab area ensures that an accidental spill will not lead to the student's receiving an electrical shock. Option B is incorrect because although wearing safety goggles and aprons is a safety procedure, it is less specific and important during an electrical experiment compared with the danger of the liquids' electrical conductivity. Option C is incorrect. Although disposing of chewing gum is a safety procedure, it is less specific and important during an electrical experiment compared with the danger of the liquids' electrical conductivity. Option D is incorrect because although keeping loose hair and clothing tied back during the lab activity is a safety procedure, it is less specific and important during an electrical experiment compared with the danger of the liquids' electrical conductivity. Clothing and hair do not transmit electricity very well so they are not electrical risks. They may however reduce the field of view and have negative interactions with the material and equipment on the worktable.

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Use the tables below to answer the question that follows.

Device	Power Rating
Vacuum	1360 W
Spotlight	720 W

Device Amperage Rating	Power Rating
1–7 amps	16 gauge
8–10 amps	14 gauge
11–14 amps	12 gauge
14+ amps	10 gauge

43. A technician is setting up the machine shop lab and needs to use a spotlight and shop vacuum, with the requirements shown. If the lab has a 120V source, and the technician is plugging both appliances into the same extension cord in parallel, what is the minimum gauge wire the setup requires?

1. 16 gauge
2. 14 gauge
3. 12 gauge
4. 10 gauge

AnswerEnter to expand or collapse answer.Answer expanded

Option D is correct because the appliances are in parallel, the total power required is the sum of both devices, which totals 2080W. The amperage (A) is calculated by dividing the power (P) by the voltage (V): A = ^P/_V = ²⁰⁸⁰/₁₂₀ = 17.33 ampsA equals P over V equals 2080 over 120 equals 17.33 amps. Therefore a minimum of 10 gauge wire is necessary. Option A is incorrect because 16 gauge wire is the minimum wire for 1–7 amps. The total required amperage is 17.33 amps, which requires a minimum of 10 gauge — not 16 gauge — wire. Option B is incorrect because 14 gauge wire is the minimum wire for 8–10 amps. The total required amperage is 17.33 amps, which requires a minimum of 10 gauge — not 14 gauge — wire. Option C is incorrect because 12 gauge wire is the minimum wire for 11–14 amps. The total required amperage is 17.33 amps, which requires a minimum of 10 gauge — not 12 gauge — wire.

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Competency 052—The teacher understands the importance of professional development and how to apply engineering knowledge to plan, implement and assess student learning.

44. A group of eighth grade students received the following instruction from their teacher:

"Using less than 15 feet of masking tape and 110 paper straws, design a bridge that will span the two tables in the classroom and hold the weight of the electric pencil sharpener. Test to determine if plastic straws are better for building the structure than paper straws. Then try wooden frozen-dessert sticks instead of straws."

Which of the following best describes this type of activity?

1. An open-ended, project-based activity
2. A focused, project-based activity
3. A controlled experiment
4. A qualitative inquiry

AnswerEnter to expand or collapse answer.Answer expanded

Option A is correct because the activity proposed by the teacher is an intentional and planned learning experience that helps students to develop new skills and learn new information, while maintaining the positive association with play. Therefore it is a project-based activity. Because there are many ways to complete the activity and many potential outcomes, it is also open-ended. Option B is incorrect because even if the activity proposed by the teacher is a project-based activity, the teacher does not explain how to build the bridge. Since the students are free to devise their personal solution, the activity is not focused. Option C is incorrect because the activity proposed by the teacher is not based on a defined repeatable procedure and the consequent logical analysis of the results. Option D is incorrect because qualitative inquiry means studying cases in their natural settings and then subjecting the resulting data to analytical induction.

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