Engineering

An annular aluminum fin of rectangular profile is attached to a circular tube having an outside diameter of 25 mm and a surface temperature of 250C. The fin is 1 mm thick and 10 mm long, and the temperature and the convection coefficient associated with the adjoining fluid are 25C and 25W/m2 .K, respectively.a) What is the heat loss per fin? What is the fin efficiency?b) If 200 such fins are spaced at 5-mm increments along the tube length, what is the heat loss per meter of tube length?c) If the tube had no fins, what would be the heat loss per meter of tube length? d) Using this result and that from part (b), what is the "fin array effectiveness"?
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If a signal is transmitted at a power of 250 mWatts (mW) and the noise in the channel is 10 uWatts (uW), if the signal BW is 20MHz, what is the maximum capacity of the channel?
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Two large, nonconducting plates are suspended 8.25 cm apart. Plate 1 has an area charge density of + 86.8 C/m2 , and plate 2 has an area charge density of + 23.6 C/m2 . Treat each plate as an infinite sheet. Two parallel vertical lines are horizontally separated from each other. Each line represents a nonconducting plate. The plate on the left is labeled plate 1, and the plate on the right is labeled plate 2. The region of space to the left of plate 1 is labeled region A. The region of space between the two plates is labeled region B. The region to the right of plate 2 is labeled region C. How much electrostatic energy U E is stored in 2.29 cm3 of the space in region A?
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An advantage presented by Straight in space is that___.
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A small manufacturing plant is located 2 km down a transmission line, which has a series reactance of 0.5 /km. The line resistance is negligible. The line voltage at the plant is 480/08 V (rms), and the plant consumes 120 kW at 0.85 power factor lagging. Determine the voltage and power factor at the sending end of the transmission line by using.a. Complex power approachb. Circuit analysis approach.
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Water is the working fluid in an ideal Rankine cycle. The pressure and temperature at the turbine inlet are 1200 lbf /in^2 and 1100F, respectively, and the condenser pressure is 140 lbf/in^2 The mass flow rate of steam entering the turbine is 1.4 x 10^6 lb/h. The cooling water experiences a temperature increase from 60 to 80F, with negligible pressure drop, as it passes through the condenser. Determine for the cycle:(a) the net power developed, in Btu/h(b) the thermal efficiency.(c) the mass flow rate of cooling water, in lb/h.
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Which description defines the mechanical advantage of a simple lever?A.the ratio of the total lever length to the length of the effort arm B. the ratio of the length of the load arm to the length of the effort arm C. the ratio of the length of the effort arm to the length of the load arm D. the ratio of the length of the load arm to the total lever length E. the ratio of the length of the effort arm to the total lever length
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A microwave transmitter has an output of 0.1 W at 2 GHz. Assume that this transmitter is used in a microwave communication system where the transmitting and receiving antennas are parabolas, each 1.2 m in diameter. a. What is the gain of each antenna in decibels
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The current entering the positive terminal of a device is i(t)= 6e^-2t mA and the voltage across the device is v(t)= 10di/dtV.( a) Find the charge delivered to the device between t=0 and t=2 s.( b) Calculate the power absorbed.( c) Determine the energy absorbed in 3 s.
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Working as a team to design a skyscraper would most satisfy which of these personal benefits of work? for odyssey1.a want2.being with others3.feeling respected4.earning money
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A bus travels the 100 miles between A and B at 50 mi/h and then another 100 miles between B and C at 70 mi/h. The average speed of the bus for the entire 200-mile trip is: a. More than 60 mi/h. b. Equal to 60 mi/h. c. Less than 60 mi/h.
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A three-phase line with an impedance of (0.2 1 j1.0) /phase feeds three balanced three-phase loads connected in parallel. Load 1: Absorbs a total of 150 kW and 120 kvar. Load 2: Delta connected with an impedance of (150 2 j48) /phase. Load 3: 120 kVA at 0.6 PF leading. If the line-to-neutral voltage at the load end of the line is 2000 v (rms), determine the magnitude of the line-to-line voltage at the source end of the line.
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Water is boiled at 1 atm pressure in a coffee maker equipped with an immersion-type electric heating element. The coffee maker initially contains 1 kg of water. Once boiling started, it is observed that half of the water in the coffee maker evaporated in 12 min. If the heat loss from the coffee maker is negligible, what is the power rating of the heating element?
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The stiffness of an axially loaded round bar is ______ and its flexibility is ______. The stiffness of torsionally loaded round bar is_______ and its flexibility is_______.
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A rectangular swimming pool 50 ft long, 25 ft wide, and 10 ft deep is filled with water to a depth of 8 ft. Use an integral to find the work required to pump all the water out over the top. (Take as the density of water =62.4lb/ft3.)
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Using Python, have your program do the following, using loops (no recursion)1. Have the user repeatedly enter integers until they enter a negative number. At that point stop inputting and proceed to the output described in step two. Note: The negative number that terminates the input is not included in any of these results.2. When the input is done, display the following if there was at least one valid (non -negative) number entered:(a) The sum of the numbers entered in that loop(b) How many numbers were entered(c) The average of those numbers to two places (avoid integer division.)(d) The lowest number input(e) The highest number inputIf there were no (valid) numbers entered, make sure your code displays the message "no valid numbers entered" (and avoids dividing by 0) instead of displaying a - e below.
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(1.24) Consumer Reports is doing an article comparing refrigerators in their next issue. Some of the characteristics to be included in the report are the brand name and model; whether it has a top, bottom, or side-by-side freezer; the estimated energy consumption per year (kilowatts); whether or not it is Energy Star compliant; the width, depth, and height in inches; and both the freezer and refrigerator net capacity in cubic feet. The "Height" is categorical variable, quantitative variable, or individuals
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Based on the graphs of stress-strain from the V-MSE site, how would you characterize the general differences between polymers and alloys in terms of mechanical properties?a. Alloys are stronger, stiffer, but less ductile.b. Polymers have a higher toughness.c. Alloys have lower Youngs Modulus.d. The properties overlap so you cant really make any general statements.
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An electric field is expressed in rectangular coordinates by E = 6x2ax + 6y ay +4az V/m.Find:a) VMN if point M and N are specified by M(2,6,1) and N(-3, -3, 2).b) VM if V = 0 at Q(4, -2, -35)c) VN if V = 2 at P(1,2,4).Please show all steps
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Which of the following can be used as a case label in a switch-case statement? Please select all that apply.Assume that FIVE is a constant int and five is an int.#define FIVE 5int five = 5;a. fiveb.FIVEc.5d.five++e. FIVE + 1
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Compute the number of kilo- grams of hydrogen that pass per hour through a 6-mm-thick sheet of palladium having an area of 0.25 m^2 at 600C. Assume a diffusion coefficient of 1.7 x 10^8 m^2/s, that the concentrations at the high- and low-pressure sides of the plate are 2.0 and 0.4 kg of hydrogen per cubic meter of palladium, and that steady-state conditions have been attained.
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Multi lane roads use __ to divide lanes of traffic moving in the same direction. A. White linesB. Yellow linesC. Diagonal stripesD. Orange stripes
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In creating C++ applications, you have the ability to utilize various formatting functions in the iostream library. What are some of the formatting vulnerabilities that can be encountered in using the iostream library in C++?
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What are the purposes of the various types of drawings used for the design and erection of steel framed buildings?
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