Thinking Like an Engineer: An Active Learning Approach (4th Edition)
4th Edition
ISBN: 9780134639673
Author: Elizabeth A. Stephan, David R. Bowman, William J. Park, Benjamin L. Sill, Matthew W. Ohland
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 11, Problem 3RQ
- 3. An engineer is conducting tests of two prototype toothbrush sanitizers that use ultraviolet radiation to kill pathogenic organisms while the toothbrush is stored. The engineer is trying to determine the minimum power needed to reliably kill pathogens on toothbrushes. Several toothbrushes are treated with a mix of bacteria, fungi, and viruses typically found in the human mouth, and then each is placed in one of the sanitizers for six hours at a specific power level (P). After six hours in the sanitizers, the viable pathogens remaining (R) on each toothbrush are assayed. Create a proper plot of the following experimental data set.
| Power (P) [W] | 15 | 28 | 35 | 50 | |
| Pathogens remaining (R) [%] | Sanitizer A | 51 | 40 | 29 | 7 |
| Sanitizer B | 59 | 42 | 22 | 8 | |
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
The initial cost of a proposed heat recovery system is $375,000. The annual operation andmaintenance costs are projected to be $12,000. The salvage value of the system at the end of itsuseful life (projected to be 30 years) is $60,000. The annual savings in fuel costs resulting fromthis system are estimated to be $55,000 per year.a. Assuming annual compounding, determine the rate of return for this heat recovery system.b. If management has set the MARR to be 15% for a heat recovery system like this, what is themaximum initial cost that can be spent on the system (assuming that all other costs and incomesare the same)?
The initial cost of a machine for a production facility is $225,000. The machine is expected tolast for 10 years with no salvage value. The company’s tax rate is 49% and SLD is used todepreciate the machine. For this type of depreciation, the tax life of the machine is considered 8years and its salvage value is $5,000. The after-tax rate of return is 14.3%. Determine the uniformannual before-tax cash flow.
Three alternatives are being considered for an air cleaning system. All three systems have a lifeof 10 years with no salvage value. System A has an initial cost of $29,000. During the first fiveyears of operation, the annual costs to operate system A are $5,000. During the second five years,the annual cost of system A increases to $16,000. System B has an initial cost of $43,000. Theannual cost to operate system B is $4,000, however, after the first year, this cost increases by$1,600 per year. System C has an initial cost of $58,000 with an annual cost of $2,400. System Crequires two upgrades: one during year 4 which costs $6,000, and the other during year 8 whichcosts $3,000. The MARR for this project is 17%. Determine which air cleaning system should beinstalled based on an economic analysis.
Chapter 11 Solutions
Thinking Like an Engineer: An Active Learning Approach (4th Edition)
Ch. 11.2 - In the following experimental data plot, identify...Ch. 11.2 - In the following experimental data plot, identify...Ch. 11.2 - In the following theoretical data plot, identify...Ch. 11.2 - In the following theoretical data plot, identify...Ch. 11.4 - Use the graph to answer the following questions....Ch. 11.5 - Use the graph to answer the following questions....Ch. 11.6 - We assume that the current through two...Ch. 11.6 - You are working for a tire manufacturer, producing...Ch. 11.6 - You want to install a solar panel system on your...Ch. 11 - Joules first law relates the heat generated to...
Ch. 11 - Data for a wind turbine is shown below. Use the...Ch. 11 - There is a large push in the United States to...Ch. 11 - Your team has designed three tennis ball...Ch. 11 - Plot the following pairs of functions on a single...Ch. 11 - Plot the following pairs of functions on a single...Ch. 11 - You need to create a graph showing the...Ch. 11 - The decay of a radioactive isotope can be modeled...Ch. 11 - In researching alternate energies, you find that...Ch. 11 - The following graph applies to ICA 11-10 to ICA...Ch. 11 - The following graph applies to ICA 11-10 to ICA...Ch. 11 - The following graph applies to ICA 11-10 to ICA...Ch. 11 - The following graph applies to ICA 11-10 to ICA...Ch. 11 - The following graph applies to ICA 11-10 to ICA...Ch. 11 - The following graph applies to ICA 11-10 to ICA...Ch. 11 - Use the following graph to determine which...Ch. 11 - The following graph shows the power delivered to a...Ch. 11 - The music industry in the United States has had a...Ch. 11 - You are working for a chemical manufacturer,...Ch. 11 - Use the accompanying graph to answer the following...Ch. 11 - A company designs submersible robots with a new...Ch. 11 - Your company is manufacturing a complex part from...Ch. 11 - For questions 1 through 10, your instructor will...Ch. 11 - 2. Due to increased demand, an industrial engineer...Ch. 11 - 3. An engineer is conducting tests of two...Ch. 11 - 4. Several reactions are carried out in a closed...Ch. 11 - 5. The following experimental data are collected...Ch. 11 - 6. If an object is heated, the temperature of the...Ch. 11 - 7. Eutrophication is the result of excessive...Ch. 11 - 8. In the 1950s, a team at Los Alamos National...Ch. 11 - Prob. 9RQCh. 11 - 10. One of the 22 named, derived units in the...Ch. 11 - Shown are graphs of the altitude in meters, and...Ch. 11 - Answer the following questions using the graph....Ch. 11 - Answer the following questions using the graph....Ch. 11 - In a simple electric circuit, the current (I) must...Ch. 11 - In a hard drive design, the faster the disk spins,...Ch. 11 - We have decided to become entrepreneurs by raising...Ch. 11 - As an engineer, suppose you are directed to design...Ch. 11 - We have obtained a contract to construct metal...Ch. 11 - Your company has developed a new high-mileage...Ch. 11 - One of the 14 Grand Challenges for Engineering as...Ch. 11 - You are an engineer for a plastics manufacturing...Ch. 11 - When a wine generator is installed there is a...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- Show all work as much as you can and box out answersarrow_forwardShow as much work as possible and box out answers pleasearrow_forwardon-the-job conditions. 9 ±0.2- 0.5 M Application questions 1-7 refer to the drawing above. 1. What does the flatness tolerance labeled "G" apply to? Surface F A. B. Surfaces E and F C. Surfaces D, E, H, and I D. The derived median plane of 12 +0.2 0.5 0.5 CF) 20 ±0.2 0.1 7. O 12 ±0.2- H 0.3 ASME Y14.5-2009arrow_forward
- elements, each with a length of 1 m. Determine the temperature on node 1, 2, 3, 4. 3. Solve the strong form analytically (you may choose Maple, MATLAB or Mathematica to help you solve this ODE). Compare the FE approximate temperature distribution through the block against the analytical solution. 1 (1) 200 °C 2 (2) 3 m 3 (3)arrow_forwardCompute the horizontal and vertical components of the reaction at the pin A. B A 30° 0.75 m 1 m 60 N 0.5 m 90 N-marrow_forwardA particle is held and then let go at the edge of a circular shaped hill of radius R = shown below. The angular motion of the particle is governed by the following ODE: + 0.4 02 - 2 cos 0 + 0.8 sin 0 = 0 where is the angle in rad measured from the top (CCW: +), ė 5m, as = wis the velocity in rad/s, ==a is the angular acceleration in rad/s². Use MATLAB to numerically integrate the second order ODE and predict the motion of the particle. (a) Plot and w vs. time (b) How long does it take for the particle to fall off the ring at the bottom? (c) What is the particle speed at the bottom. Hint v = Rw. in de all questions the particles inside the tube. /2/07/25 Particle R 0 0 R eled witharrow_forward
- If FA = 40 KN and FB = 35 kN, determine the magnitude of the resultant force and specify the location of its point of application (x, y) on the slab. 30 kN 0.75 m 90 kN FB 2.5 m 20 kN 2.5 m 0.75 m FA 0.75 m 3 m 3 m 0.75 marrow_forwardThe elastic bar from Problem 1 spins with angular velocity ω about an axis, as shown in the figure below. The radial acceleration at a generic point x along the bar is a(x) = ω 2 x. Under this radial acceleration, the bar stretches along x with displacement function u(x). The displacement u(x) is governed by the following equations: ( d dx (σ(x)) + ρa(x) = 0 PDE σ(x) = E du dx Hooke’s law (2) where σ(x) is the axial stress in the rod, ρ is the mass density, and E is the (constant) Young’s modulus. The bar is pinned on the rotation axis at x = 0 and it is also pinned at x = L. Determine:1. Appropriate BCs for this physical problem.2. The displacement function u(x).3. The stress function σ(x).arrow_forwardThe heated rod from Problem 3 is subject to a volumetric heatingh(x) = h0xLin units of [Wm−3], as shown in the figure below. Under theheat supply the temperature of the rod changes along x with thetemperature function T(x). The temperature T(x) is governed by thefollowing equations:(−ddx (q(x)) + h(x) = 0 PDEq(x) = −kdTdx Fourier’s law of heat conduction(4)where q(x) is the heat flux through the rod and k is the (constant)thermal conductivity. Both ends of the bar are in contact with a heatreservoir at zero temperature. Determine:1. Appropriate BCs for this physical problem.2. The temperature function T(x).3. The heat flux function q(x).arrow_forward
- A heated rod of length L is subject to a volumetric heating h(x) = h0xLinunits of [Wm−3], as shown in the figure below. Under the heat supply thetemperature of the rod changes along x with the temperature functionT(x). The temperature T(x) is governed by the following equations:(−ddx (q(x)) + h(x) = 0 PDEq(x) = −kdTdx Fourier’s law of heat conduction(3)where q(x) is the heat flux through the rod and k is the (constant)thermal conductivity. The left end of the bar is in contact with a heatreservoir at zero temperature, while the right end of the bar is thermallyinsulated. Determine:1. Appropriate BCs for this physical problem.2. The temperature function T(x).3. The heat flux function q(x).arrow_forwardCalculate the mean piston speed (in mph) for a Formula 1 engine running at 14,750 rpm with a bore of 80mm and a stroke of 53mm. Estimate the average acceleration imparted on the piston as it moves from TDC to 90 degrees ATDCarrow_forwardCalculate the compression ratio of an engine with a stroke of 4.2inches a bore of 4.5 inches and a clearance volume of 6.15 cubic inches. Discuss whether or not this is a realistic compression ratio for a street engine and what octane rating of fuel it would need to run correctlyarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning
Refrigeration and Air Conditioning Technology (Mi...Mechanical EngineeringISBN:9781305578296Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill JohnsonPublisher:Cengage Learning
Principles of Heat Transfer (Activate Learning wi...
Mechanical Engineering
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Cengage Learning
Refrigeration and Air Conditioning Technology (Mi...
Mechanical Engineering
ISBN:9781305578296
Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher:Cengage Learning
Understanding Conduction and the Heat Equation; Author: The Efficient Engineer;https://www.youtube.com/watch?v=6jQsLAqrZGQ;License: Standard youtube license