Master Engineering with Fun Quizzes & Brain Teasers!

A certain heat pump produces 200 kW of heating for a 293 K heated zone while only using 75 kW of power and a heat source at 273 K. Calculate the COP of this device as well as the theoretical maximum COP
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Guys i need help and some ones please help me Engineering Design:Question 10Which option describes the engineering design process?Select one:1. A series of steps engineers use to identify constraints.2. A series of steps engineers use to decide which solution is best.3. A series of steps engineers use to test what they build.4. A series of steps engineers use to solve problems.
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Deep-ocean fish cannot survive in shallow water, because the waterpressure is too low. Donovan is working on a container to bring deep-ocean fish to the surface successfully. He has studied alternativedesigns, decided on a best one, and built a prototype.Which option describes what Donovan is MOST likely to do next?Select one:1. Communicate the prototype to others.2. Build another prototype, for the next-best idea.3. Test the prototype against the design criteria.4. Write down possible problems about the prototype
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A single crystal of a metal that has the FCC crystal structure is oriented such that a tensile stress is applied parallel to the [100] direction. If the critical resolved shear stress for this material is 1.98 MPa, calculate the magnitude of applied stress necessary to cause slip to occur on the (111) plane in the direction.
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Why is it important to always be wearing a personal flotation device (PFD) when in or around the water?Failure to wear a PFD while boating can lead to harsh finesWearing a PFD reduces the chances of capsizing your vesselA PFD takes some time to fit properly especially in an emergencyD Wearing a PFD will help protect you from sunbum
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A hydroelectric turbine passes 1.7 million gal/min through its blades. If the average velocity of the flow in the circular cross-sectional conduit leading to the turbine is not to exceed 34 ft/s, determine the minimum allowable diameter of the conduit.
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Air flows steadily through a variable sized duct in a heat transfer experiment with a speed of u = 20 2x, where x is the distance along the duct in meters, and u is in m/s. Because of heat transfer out of the duct, the air temperature, T, within the pipe cools as it goes downstream, according to T = 200 - 5x C. As they flow past the section at x= 3 meters, (a) determine the acceleration; (b) Determine the rate of change of temperature of air particles
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The velocity of the 7.7-kg cylinder is 0.49 m/s at a certain instant. What is its speed v after dropping an additional 1.28 m? The mass of the grooved drum is m = 10.5 kg, its centroidal radius of gyration is = 300 mm, and the radius of its groove is ri = 275 mm. The frictional moment at O is a constant 18.4 Nm.
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Hey, I have a question, I was thinking that if you have engineering skills or drawing skill you could help me to start a project on scratch, which would be a life or WW3 simulation. Comment or answer if you would like to help.
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Mechanic... Mechanical Engineer... What's the difference?Instructions: Answer the question below with at least TWO complete sentences.
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A DC servomotor has a torque constant of 0.075 N-m/A and a voltage constant of 0.12 V/(rad/sec). The armature resistance is 2.5 Ohm. A terminal voltage of 24 V is used to operate the motor. Determine:a) the starting torque generated by the motor just as the voltage is applied.b) the maximum speed at a torque of zero.c) the operating point of the motor when it is connected to a load whose torque characteristic is proportional to speed with a constant of proportionality = 0.0125 N-m/(rad/sec).
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A work cell is currently operated 2000 hr/yr by a human worker who is paid an hourly rate of $23.00, which includes applicable overhead costs. One work unit is produced in a cycle time of 4.8 min. Management would like to increase output to meet increasing demand and a robot cell is being considered as a replacement for the present manual cell. The cycle time of the proposed cell would be reduced to 4.0 min. The installed cost of the robot plus supporting equipment is $120,000. Power and other utilities to operate the robot will be $0.30/hr, and annual maintenance costs are $2500. Determine:a. the number of parts produced annually by the manually operated cell.b. cost per part produced.c. how does the cost per part of the robot cell compare with your answer in part (b), given a 4-year service life, 10% rate of return, and no salvage value.
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One method that is used to grow nanowires (nanotubes with solid cores) is to initially deposit a small droplet of a liquid catalyst onto a flat surface. The surface and catalyst are heated and simultaneously exposed to a higher-temperature, low-pressure gas that contains a mixture of chemical species from which the nanowire is to be formed. The catalytic liquid slowly absorbs the species from the gas through its top surface and converts these to a solid material that is deposited onto the underlying liquid-solid interface, resulting in construction of the nanowire. The liquid catalyst remains suspended at the tip of the nanowire. Consider the growth of a 15-nm-diameter silicon carbide nanowire onto a silicon carbide sururface. The surface is maintained at a temperature of Ts = 2400 K and the particular liquid catalyst that is used must be maintained in the range 2400 K Tc 3000 K to perform its function. Determine the maximum length of a nanowire that may be grown for conditions characterized by h = 105 W/m2.K and T[infinity] = 8000 KT. Assume properties of the nanowire are the same as for bulk silicon carbide.
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Which courses might a mechanical engineer take in college
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The recommended time weighted average air concentration for occupational exposure to water soluble hexavalent chromium (Cr VI) is 0.05 mg m3. This concentration is based on an assumption that the individual is generally healthy and is exposed for 8 hours per day, 5 days per week, 50 weeks per year, over a working lifetime (that is from age 18 to 65 years). Assuming a body weight of 78 kg and inhalation rate of 15.2 m3 d1 over the working life of the individual, what is the lifetime (75 years) CDI?
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A single phase, 50-KVA, 2400-240-volt, 60 Hz distribution transformer has the following parameters: Resistance of the 2400-volt winding Ri=0.75 ohm Resistance of the 240-volt winding R=0.0075 ohm Leakage reactance of the 2400-volt winding X:=1 ohm Leakage reactance of the 240-volt winding X2=0.01 ohm Core loss resistance on the 2400 side Rc=733.5 ohms Magnetizing reactance on the 2400 side X=4890 ohms a. Draw the equivalent circuit referred to the high voltage side and referred to the low- voltage side. Label the impedances numerically. b. The transformer is used as a step-down transformer at the load end of a feeder having impedance of (0.5+j2.0) ohms. Determine the voltage V. at the ending end of the feeder when the transformer delivers rated load at rated secondary voltage and 0.8 laggin power factor. Neglect the "exciting current" l. of the transformer (this is the current into the parallel Rc/jXm combination), which is another way of saying that you should use what we called in class the "approximate circuit #2).
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6. QuestionWhich statements are true about routers? Check all that apply.A router can only send data to another computer that's on the same network.A router is a set of components that makes up computer networking.A router connects devices together and helps direct network traffic.A router utilizes network protocols to help determine where to send data packets.7.Question
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NEEDS TO BE IN PYTHON:ISBN-13 is a new standard for indentifying books. It uses 13 digits d1d2d3d4d5d6d7d8d910d11d12d13 . The last digit d13 is a checksum, which is calculated from the other digits using the following formula:10 - (d1 + 3*d2 + d3 + 3*d4 + d5 + 3*d6 + d7 + 3*d8 + d9 + 3*d10 + d11 + 3*d12) % 10If the checksum is 10, replace it with 0. Your program should read the input as a string. Display "incorrect input" if the input is incorrect.Sample Run 1Enter the first 12 digits of an ISBN-13 as a string: 978013213080The ISBN-13 number is 9780132130806Sample Run 2Enter the first 12 digits of an ISBN-13 as a string: 978013213079The ISBN-13 number is 9780132130790
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All of the following are common causes of low engine compression except forA. too much oilB. defective valves.C. weak piston rings.D. bent pushrods
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PLZ HELP A person hired by a pharmaceutical company to streamline the companys drug production process would most likely be an electrical engineer? True or False
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The extent to which gravity exerts force on an object is known as ______. [multiple choice] velocity, mass, volume or weight
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Assignment 1: Structural Design of Rectangular Reinforced Concrete Beams for Bending Perform structural design of a rectangular reinforced concrete beam for bending. The beam is simply supported and has a span L=20 feet. In addition to its own weight the beam should support a superimposed dead load of 0.50 k/ft and a live load of 0.65 k/ft. Use a beam width of 12 inches. The depth of the beam should satisfy the ACI stipulations for minimum depth and be proportioned for economy. Concrete compressive strength fc = 4,000 psi and yield stress of reinforcing bars fy = 60,000 psi. Size of stirrups should be chosen based on the size of the reinforcing bars. The beam is neither exposed to weather nor in contact with the ground, meaning it is subjected to interior exposure. Use the reference on "Practical Considerations for Rectangular Reinforced Concrete Beams" Include references to ACI code see slides from second class Include references to Tables from Appendix A Draw a sketch of the reinforced concrete beam showing all dimensions, number and size of rebars, including stirrups.
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Martha has been running a small business for two years. She now seeks additional investment to finance her business. She has found potential investors who want to check how much Martha's business owns and owes others. Which financial statement should Martha provide to her investors? A. cash flow statement B. balance sheet C. trial balance D. journal
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Type your response in the box. Most novels include at least one important symbol. Identify at least one symbol in the novel you just finished. In 125 to 150 words, identify the symbol. State the type of symbol it is (universal or contextual), and describe its meaning. Be sure to include specific details from the story to support your answer.
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