Engineering

A bridge hand consists of 13 cards. One way to evaluate a hand is to calculate the total high point count (HPC) where an ace is worth four points, a king is worth three points, a
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Before entering an underground utility vault to do repairs, a work crew analyzed the gas in the vault and found that it contained 29 mg/m3of hydrogen sulfide. Because the allowable exposure level is 14 mg/m3, the work crew began ventilating the vault with a blower. If the volume of the vault is 160 m3and the flow rate of contaminant-free air is 10 m3/min, how long will it take to lower the hydrogen sulfide level to a level that will allow the work crew to enter? Assume the manhole behaves as a CMFR and that hydrogen sulfide is nonreactive in the time period considered.
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An insulated piston-cylinder device contains 5 L of saturated liquid water at a constant pressure of 175 kPa. Water is stirred by a paddle wheel while a current of 8 A flows for 45 min through a resistor placed in the water. If one-half of the liquid is evaporated during this constant-pressure process and the paddle-wheel work amounts to 400 kJ, determine the voltage of the source. Also, show the process on a
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What is the purpose of the following algorithm? input somenum Repeat the following steps for 14 times input variable1 if variable1 < somenum then somenum = variable1 print somenum
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The water behind Hoover Dam is 206m higher than the Colorado river below it. At what rate must water pass through the hydraulic turbines of this dam to produce 100 MW of power if the turbines are 100 percent efficient?
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A particular NMOS device has parameters VT N = 0.6 V, L = 0.8m, tox = 200 , and n = 600 cm2 /Vs. A drain current of ID = 1.2 mA is required when the device is biased in the saturation region at VGS = 3 V. Determine the required channel width of the device.
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. A steam turbine operates between 500C and 3.5 MPa to 200C and 0.3 MPa. If the turbine generates 750 kW and the heat loss is 100 kW, what is the flow rate of steam through the turbine?
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Silicon carbide nanowires of diameter 15 nm can be grown onto a solid silicon carbide surface by carefully depositing droplets of catalyst liquid onto a flat silicon carbide substrate. Silicon carbide nanowires grow upward from the deposited drops, and if the drops are deposited in a pattern, an array of nanowire fins can be grown, forming a silicon carbide nano-heat sink. Consider finned and unfinned electronics packages in which an extremely small, 10 m 10 m electronics device is sandwiched between two 100-nm-thick silicon carbide sheets. In both cases, the coolant is a dielectric liquid at 20C. A heat transfer coefficient of 1.0 105 W/m2K exists on the top and bottom of the unfinned package and on all surfaces of the exposed silicon carbide fins, which are each 300 nm long. Each nano-heat sink includes a 50 50 array of nanofins. Determine the maximum allowable heat rate that can be generated by the electronic device so that its temperature is maintained at 95C for (a) the unfinned and (b) the finned packages
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The portable lighting equipment for a mine is located 100 meters from its dc supply source. The mine lights use a total of 5 kW and operate at 120 V dc. Determine the required cross-sectional area of the copper wires used to connect the source to the mine lights if we require that the power lost in the copper wires be less than or equal to 5 percent of the power required by the mine lights.
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3. Suppose that a class named Bicycle contains a private nonstatic integer named height, a public nonstatic String named model, and a public static integer named wheels. Which of the following are legal statements in a class named BicycleDemo that has instantiated an object as Bicycle myBike new Bicycle C);? f. Bicycle. model Hurricane a. myBike height 26; b. my Bike model Cyclone g. Bicycle. int 3 3; c. myBike Wheels 3 d. my Bike .model 108; i. Bicycle wheels 2 e. Bicycle height 24; j. Bicycle yourBike myBike
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Checkpoint 4.72 Write a statement that uses a conditional expression that determines if the credits variable is less than 0. If the condition is true, assign the value 0 to the credits variable, otherwise the value of the credits variable should remain unchanged.
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g Create an array of five animals. Use a for loop to display the values stored in that array. Add two more animals to the end of that array. Sort the array and display the sorted array on the screen.
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In the casting of steel under certain mold conditions, the mold constant in Chvorinov's Rule is known to be 4.0 min/cm2, based on previous experience. The casting is a flat plate whose length = 35 cm, width = 10 cm, and thickness = 15 mm. Determine how long it will take for the casting to solidify.
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Electric heater wires are installed in a solid wall having a thickness of 8 cm and k=2.5 W/m.C. The right face is exposed to an environment with h=50 W/m2C and k'=30C, while the left face is exposed to h=75 W/m2C and T[infinity]=50C. What is the maximum allowable heat generation rate such that the maximum temperature in the solid does not exceed 300C.
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A single axial load of magnitude P = 15 kips is applied at end C of thesteel rod ABC. Knowing that E = 30 106 psi, determine the diameterd of portion BC for which the deflection of point C will be 0.05 in.
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Which statement is not correct regarding the deformation of a circular shaft in torsion? a. Cross sections remain flat. b. Longitudinal lines remain straight. c. Circular sections remain circular. d. Radial lines on the sections remain straight.
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An earthen trapezoidal channel (n = 0.025) has a bottom width of 5.0 m, side slopes of 1.5 horizontal: 1 vertical and a uniform flow depth of 1.10 m. In an economic study to remedy excessive seepage from the canal two proposals, (a) to line the sides only and, (b) to line the bed only are considered. If the lining is of smooth concrete (n = 0.012), calculate the equivalent roughness in the above two cases for a bottom slope of 0.005
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Air at 27oC and 50% relative humidity is cooled in a sensible cooling process to 18oC. The air is then heated to 45oC in a sensible heating process. Finally, the air experiences an adiabatic saturation process that increases the relative humidity back to 50%. Find the specific energy that is removed when the air is cooled to 18C.
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A ship tows a submerged cylinder, 1.5 m in diameter and 22 m long, at U = 5 m/s in fresh water at 20C. Estimate the towing power in kW if the cylinder is (a) parallel, and (b) normal to the tow direction.
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A biotechnology company produced 225 doses of somatropin, including 11 which were defective. Quality control test 15 samples at random, and rejects the batch if any of the random samples are found defective. What is the probability that the batch gets rejected?
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With reference to the NSPE Code of Ethics, which one of the following statements is true regarding the ethical obligations of the engineers involved in the VW Emissions Cheating Scandal. a. The VW engineers involved conducted themselves honorably, responsibly, ethically, and lawfully so as to enhance the honor, reputation, and usefulness of the profession. b. As faithful agents and trustees of Volkswagen the engineers involved could not ethically report the emissions cheating violations to public authorities. c. The VW engineers involved were ethically obligated to hold paramount the health, welfare and safety of the public even if their supervisors directed them to implement software and hardware that enabled cheating on the emissions testing software. d. The VW engineers involved were not ethically obligated to report to their supervisors and to upper management the emissions cheating violations being implemented in the control system hardware and software.
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A large tower is to be supported by a series of steel wires. It is estimated that the load on each wire will be 11,100 N (2500 lb f ). Determine the minimum required wire diameter assuming a factor of safety of 2 and a yield strength of 1030 MPa (150,000 psi).
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A city engineer knows that she will need $25 million in 3 years to replace toll booths on a toll road in the city. Traffic on the road is estimated to be 20 million vehicles per year. How much per vehicle should the toll be to cover the cost of the toll booth replacement project? Interest is 10%.
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A pipe of inner radius R1, outer radius R2 and constant thermal conductivity K is maintained at an inner temperature T1 and outer temperature T2. For a length of pipe L find the rate at which the heat is lost and the temperature inside the pipe in the steady state.
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