Engineering

def find_missing_letters(sentence): the input sentence is an array/list (created from normalize()) returns a sorted list of letters that are NOT in the sentence use the built in Python type set to solve (see previous lesson) def find_missing letters algorithm(sentence): the input sentence is an array/list (created from normalize()) returns a sorted array of letters that are NOT in the sentence you must NOT use the set type Hints for find_missing_letters algorithm: create your own algorithm and use only the data types (other than set) that we have discussed the set datatype is removed during the running of the tests (so don't use it) the output should be the same as that from find_missing_letters (easy to test) if you find yourself writing over 30 lines of code, you are proba
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An insulated piston-cylinder device initially contains 300 L of air at 120 kPa and 17 oC. Air is now heated for 15 min by a 200-w resistance heater placed inside the cylinder. The pressure of air is maintained constant during this process. Determine the entropy change of air assuming (a) ) constant specific heats and (b) ) variable specific heats.
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A coal-fired power plant is burning bituminous coal that has an energy content of 12,000 Btu/lb. The power plant is burning the coal at a rate of 110 lb/s. The efficiency of the powerplant is 33%, which means that 67% of the total energy from the coal is lost as waste heat. a. A new heat exchanger is installed that is capable of using 0.12% of the waste heat to heat an air stream for use in another process in the plant. The air enters the heat exchanger at a volumetric flow rate of 2,000 acfm at 298 K and 1 atm. Assuming the heat exchanger is 90% efficient (i.e., 90% of the heat supplied to the heat exchanger is transferred to the air stream), at what temperature will the air leave the heat exchanger, assuming an exit pressure of 1 atm? Use an average specific heat of 0.244 Btu/lb-R. b. What will be the volumetric flow rate of the gas leaving the heat exchanger (in units of acfm)? c. If the air exiting the heat exchanger has a moisture content of 12% (v/v), what is the moisture-corrected dry flow rate (in units of dry standard cubic meters per minute) at STP (1 atm, 298 K)?
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There is a large push in the united states currently to convert incandescent light bulbs more energy-efficient technologies, including compact fluorescent lights and light-emitting diodes. The lumen [lm] is the SI unit of luminous flux, a measure of the perceived power of light. To test the power usage, you runan experiment and measure the following data. Create a proper plot of these data, with electrical consumption (EC) on the ordinate.Electrical Consumption [W]Incandescent CompactLuminous Flux [lm] 120 Volt Fluorescent80 16200 4400 38 8600 55750 68 131,250 181,400 105 19
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1. How many pieces of 12-1/2" long wood can be cut from a piece ofwood that is 39-3/4" long? *o A. 2o B.3o C.6OD.7
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4. Three routes connect an origin and a destination with performance functions tl = 8 + 0.5x1, t2 = 1 + 2x2, and t3 = 3 + 0.75x3, with the x's expressed in thousands of vehicles per hour and the t's expressed in minutes. If the peak-hour traffic demand is 3400 vehicles, determine user-equilibrium traffic flows. Note: there are 823 vehicles that must pass by a daycare in route 1.
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An engineer working in an electronics lab connects a parallel-plate capacitor to a battery, so that the potential difference between the plates is 240 V. Assume a plate separation of d 1.77 cm and a plate area of A-25.0 cm. when the battery is removed, the capacitor is plunged into a container of distilled water. Assume distilled water is an insulator with a dielectric constant of 80.0(a) Calculate the charge on the plates (in pC) before and after the capacitor is submerged. (Enter the magnitudes.) before pC after Q pC (b) Determine the capacitance (in F) and potential difference (in V) after immersion. (c) Determine the change in energy (in nJ) of the capacitor nJ (d) What If? Repeat parts (a) through (c) of the problem in the case that the capacitor is immersed in distilled water while still connected to the 240 V potential difference Calculate the charge on the plates (in pC) before and after the capacitor is submerged. (Enter the magnitudes.) before Q, - after Q Determine the capacitance (in F) and potential difference (in V) after immersion. pC pC Determine the change in energy (in nJ) of the capacitor. nJ
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Three 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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At 500oC, the diffusion coefficient of Cu in Ni is 1.3 x 10-22 m2/s, and the activation energy for diffusion is 256,000 J/mol. From this information, determine the diffusion coefficient of Cu in Ni at 900 oC . (R = 8.314 J/(mol K)) 0oC = 273 K
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The maximum compressive load experienced by the same truss member would occur when the live load is __________. The magnitude of the maximum compressive load would be __________ the magnitude of the maximum tensile load.
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You are running a software company and have a series of n jobs that must be pre-processed first on a supercomputer before being moved to a smaller PC. You have only one super- computer, but you have n PCs so the second stage can be performed in in parallel. More specifically, your jobs are described as J- (s1f), J2 (22).., Jn-(Sn,n), where job J needs si units of time to be pre-processed on the super-computer and fi units of time on the PC You need to work out an order in which to give the jobs to the super-computer. As soon as the first job is done on the super-computer, it can be moved to the PC for finishing; at that point a second job can be given to the super-computer; when the second job is done it can go straight to a PC since the PCs can work in parallel, and so on. So if the jobs are processed in the order given, job J finishes at time (sk) fi. A schedule is an ordering of the jobs to be given to the super-computer. The completion time is the point at which all jobs have finished being processed on the PCs. We wish to minimize the completion time. (a) Give an efficient (greedy!) algorithm for computing the optimal order in which to proces the jobs so that the completion time is minimized. (b) Describe the greedy choice your algorithm makes and show that it is correct.
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The heat required to raise the temperature of m (kg) of a liquid from T1 to T2 at constant pressure is Z T2CpT dT (1) In high school and in first-year college physics courses, the formula is usually given asQ H m Q mCp T mCpT2 T1 (2)T1(a) What assumption about Cp is required to go from Equation 1 to Equation 2? (b) The heat capacity (Cp) of liquid n-hexane is measured in a bomb calorimeter. A small reaction flask (the bomb) is placed in a well-insulated vessel containing 2.00L of liquid nC6H14 at T 300 K. A combustion reaction known to release 16.73 kJ of heat takes place in the bomb, and the subsequent temperature rise of the system contents is measured and found to be 3.10 K. In a separate experiment, it is found that 6.14kJ of heat is required to raise the temperature of everything in the system except the hexane by 3.10 K. Use these data to estimate Cp[kJ/(mol K)] for liquid n-hexane at T 300 K, assuming that the condition required for the validity ofEquation 2 is satisfied. Compare your result with a tabulated value.
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Eureka is a telephone and Internet-based concierge services that specializes in obtaining things that are hard to find (e.g. Super Bowl tickets, first edition books from the 1500s, Faberge eggs). It currently employs 60 staff members who collectively provide 24-hour coverage (over three shifts). They answer the phones and respond to requests entered on the Eureka! Web site. Much of their work is spent on the phone and on computers searching on the Internet. The company has just leased a new office building and is about to wire it. They have bids from different companies to install (1) 100-Base T network (2) Wi-Fi network What would you recommend
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Set up the differential equation that describes the motion under the assumptions of this section. Solve the differential equation. State whether the motion of the spring-mass system is harmonic, damped oscillation, critically damped, oroverdamped. If the motion is a damped oscillation, rewrite in the form (22).33. The spring-mass system has an attached mass of 10 g. The spring constant is30 g/s 2 . A dashpot mechanism is attached, which has a damping coefcient of 40 g/s. The mass is pulled down and released. At time t = 0, the mass is 3 cmbelow the rest position and moving upward at 5 cm/s.34. A long spring has a mass of 1 slug attached to it. The spring stretches 16/13 ftand comes to rest. The damping coefcient is 2 slug/s. The mass is subjected toan impulsive force at time t = 0, which imparts a velocity of 5 ft/s downward.
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Air at 26 kPa, 230 K, and 220 rn/s enters a turbojet engine in flight. The air mass flow rate is 25 kg/s. The compressor pressure ratio is 11, the turbine inlet temperature is 1400 K, and air exits the nozzle 26 kPa. The diffuser and the nozzle processes are isentropic, the compressor and turbine have isentropic efficiencies of 85% and 90%, respectively. There is no pressure drop for flow through the combustor. Kinetic energy is negligible everywhere except at the diffuser inlet and the nozzle exit. On the basis of air-standard analysis, determine: (a)the pressures and temperatures at each state, (b)the rate of heat addition to the air passing through the combustor, (c) the velocity at the nozzle exit.
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For a bronze alloy, the stress at which plastic deformation begins is 275 MPa and the modulus of elasticity is 115 GPa. If the original specimen length is listed above, what is the maximum length to which it may be stretched without causing plastic deformation
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A sailboat is operating under sail at night. Which of these lights should be used?orange masthead lightblue sternlightyellow masthead lightwhite sternlight
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g A plane stress element has components sigma x = 160 MPa, tau xy = 100 MPa (CW). Determine the two values pf sigma y for which the maximum shear stress is 73 MPa.
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List four things that should be done during a thorough inspection of the brake fluid.
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An NMOS amplifier is to be designed to provide a 0.50-V peak output signal across a 50- k load that can be used as a drain resistor. If a gain of at least 5 V/V is needed, what gm is required?
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Part A - Transmitted power A solid circular rod is used to transmit power from a motor to a machine. The diameter of the rod is D = 2.5 in and the machine operates at = 170 rpm . If the allowable shear stress in the shaft is 10.4 ksi , what is the maximum power transmissible to the machine? Express your answer with appropriate units to three significant figures.
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Consider a Cournot game between two firms. The firms face an inverse demand function described by the equation P(Q) = Q if Q , P(Q) = 0 if Q > , where P is the price of output and Q is the total output produced by the two firms. Firm 1 produces its output q1 at a constant unit cost c1 (i.e, the total cost to firm 1 of producing
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A car is traveling at 70 mi/h on a level section of road with good, wet pavement. Its antilock braking system (ABS) only starts to work after the brakes have been locked for 100 ft. If the driver holds the brake pedal down completely, immediately locking the wheels, and keeps the pedal down during the entre process, how many feet will it take the car to stop from the point of initial brake application? (The braking efficiency is 80% with the ABS not working and 100% with the ABS working. Use theoretical stopping distance and ignore air resistance. Let frl = 0.02 when the brakes are locked, but compute the frl once the ABS becomes active.)
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a triangle is defined by the three vertices. write the following functions of the triangle class assume that the point class has already been written for you you may add helper functions as needed
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