Engineering

Water is to be boiled at sea level in a 30-cm-diameter stainless steel pan placed on top of a 3-kW electric burner. If 60 percent of the heat generated by the burner is transferred to the water during boiling, determine the rate of evaporation of water.
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. A two-dimensional fluid motion is represented by a point vortex of strength set at distance c from an infinite straight solid boundary. Write expressions for the velocity potential and stream function in Cartesian coordinates. Derive an expression for velocity on the boundary. Draw the streamlines and plot the velocity distribution on the boundary when = and c = 1.
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While it is important to gain information on the prospect, it is relatively unimportant to gain any information on the prospects organization prior to initiating sales dialogue.ANS:FPTS:1DIF:Difficulty: EasyREF:p. 124-125OBJ:LO: 5-5
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Water flows in a tube that has a diameter of D= 0.1 m. Determine the Reynolds number if the average velocity is 10 diameters per second. (b) Repeat the calculations if the tube is a nanoscale tube with a dimeter of D= 100 nm.
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Design a database suitable for a university registrar. This database should include information about students, departments, professors, courses, which students are enrolled in which courses, which professors are teaching which courses, student grades, TA's for a course (TA's are students), which courses a department offers, and any other information you deem appropriate. Note that this question is more free-form than the questions above, and you need to make some decisions about multiplicities of relationships, appropriate types, and even what information needs to be represented.
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hree large plates are separated bythin layers of ethylene glycol and water. The top plate moves to the right at 2m/s. At what speed and in what direction must the bottom plate be moved to hold the center plate stationary?
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A piston-cylinder device contains 0.15 kg of air initially at 2 MPa and 350 C. The air is first expanded isothermally to 500 kPa, then compressed polytropically with a polytropic exponent of 1.2 to the initial pressure, and finally compressed in an isobaric process to the initial state. Determine the boundary work for each process and the net work for the cycle?
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A parallel plate capacitor has a separation of 2x10 m and free space between the plates. A 10 V battery is connected across the plates and then removed without disturbing the charge on the plates. The plates are now allowed to come together toa separation of 10% m without disturbing the charge on the plates. Fringing fields can be ignored. A) What is the voltage across the plates? B) How has the energy stored in the capacitor changed?
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The pistons of a V-6 automobile engine develop 226.5 hp. If the engine driveshaft rotational speed is 4700 RPM and the torque is 248 ftlbf, determine the shaft power, in hp, and the percentage of the developed power that is transferred to the driveshaft.
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You are an electrician on the job. The electrical blueprint shows that eight 500-W lamps are to be installed on the same circuit. The circuit voltage is 277V and is protected by a 20-A circuit breaker. A continuous-use circuit can be loaded to only 80% of its rating. Is a 20-A circuit large enough to carry this load
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100 kg of refrigerant-134a at 200 kPa iscontained in a piston-cylinder device whose volume is 12.322 m3. The piston is now moved until the volume is one-half its original size. This is done such that thepressure of the refrigerant-134a does not change. Determine (a) the final temperatureand (b) the change in the specific internal energy.
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(a) Aluminum foil used for storing food weighs about 0.3 grams per square inch. How many atoms of aluminum are contained in one square inch of the foil? (b) Using the densities and atomic weights given in Appendix A, calculate and compare the number of atoms per cubic centimeter in (i) lead and (ii) lithium.
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Design a circuit that will output HIGH when the input is a prime number larger than 2 and smaller than 16. The input should be a 4-bit binary number. Design the circuit using a 4:16 decoder and other gates.
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An asphalt mixture is placed and compacted using normal rolling procedures. Two tests are taken from the compacted mixture and checked for density. Core 1 had a density of 150 pcf and an air void content of 6.5 %. Core 2 had a density of 151 pcf. What is the air void content of core 2.
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Consider the Poisson trip generation model in Example 8.4. Suppose that a household has five members with an annual income of $150,000 and lies in a neighborhood with a retail employment of 320. What is the expected number of peak-hour shopping trips, and what is the probability that the household will make more than one peak-hour shopping trip. Process: (1) Calculate the Poisson parameter (2) Determine the probability of making zero trips and one trip; (3) subtract the values from #2 from 1 to determine probability
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Gas at a temperature of 250C with a convective coefficient 75 W/m2K flows through a packed bed of aluminum (2024) spheres that is used as a thermal energy storage system. If the initial temperature of the spheres is 25C and the diameter of each sphere is 75-mm, find the time, in seconds, required to for a sphere to reach 85% of the maximum possible thermal energy as well as the surface temperature and the centerline temperature at this time, both in C. Evaluate the properties of the aluminum (2024) at 500 K.
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Using your time efficiency function from HW1, measure the execution times of both insertion and merge sorting algorithms using the attached data files (one with 1,000 integers and the other with 1,000,000 integers ).
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An enrichment plant has a throughput of 32,000 kg U/day and produces 26,000 kg U as tails. What is the enrichment of the product if the feed is natural uranium and the tails are 0.25%
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declare integer product declare integer number product = 0 do while product < 100 display ""Type your number"" input number product = number * 10 loop display product End While
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1- If the elongation of wire BC is 0.3 mm after the force P is applied, determine the magnitude of P. The wire is made of steel with an elastic modulus of 200 GPa and has a diameter of 2 mm.
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A successful quality strategy features which of the following elements? engaging employees in the necessary activities to implement quality an organizational culture that fosters quality an understanding of the principles of quality engaging employees in the necessary activities to implement quality and an understanding of the principles of quality engaging employees in the necessary activities to implement quality, an organizational culture that fosters quality, and an understanding of the principles of quality
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A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at 30C by rejecting its waste heat to cooling water that enters the condenser at 18C at a rate of 0.25 kg/s and leaves at 26C. The refrigerant enters the condenser at 1.2 MPa and 65C and leaves at 42C. The inlet state of the compressor is 60 kPa and 34C and the compressor is estimated to gain a net heat of 450 W from the surroundings. Determine (a) the quality of the refrigerant at the evaporator inlet, (b) the refrigeration load, (c) the COP of the refrigerator
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An inventor has developed a machine that extracts energy from water and other effluents drained from apartments in a building. The machine essentially consists of a hydraulic turbine placed in the basement (level zero), through which the effluents pass before being dumped into the sewage system.(a) If the average height of an apartment relative to the location of the turbine is 30 meters and the average flow from each apartment (assume it to be water) is 100 liters per day, calculate the average power produced by the contraption if there are 100 apartments in the building. Assume ambient state to be 300 K, 1 bar.
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Ridif bar ABC is supported with a pin at A and an elastic steel rod at C. The elastic rod has a diameter of 25mm and modulus of elasticity E = 200 GPA. The bar is subjected to a uniform load q on span AC and a pointload at B. Calculate the change in length of the elastic rod. What is the vertical displacement at point B?
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