Engineering

A vertical piston-cylinder device contains water and is being heated on top of a range. During the process, 10 kJ of heat is transferred to the water, and heat losses from the side walls amount to 80 J. The piston rises as a result of evaporation, and 2 J of work is done by the vapor. Determine the change in the energy of the water for this process.
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Determine if each of the following statements is true or false: 1. Larger atoms are better nucleophiles due to polarizability. 2. The identity of the nucleophile affects the rate of an SN1 reaction. 3. SN2 reactions proceed via frontside attack. 4. Bimolecular reactions tend to be stereoselective. 5. SN2 reactions invert all stereocenters in a haloalkane. 6. Cl-, OH-, and H- are good all leaving groups. 7. Good bases tend to be good nucleophiles 8. Branching adjacent to a reacting carbon slows SN2 reactions due to steric hindrance. 9. SN1 reactions are slowed by hyperconjugation of the carbocation intermediate. 10. The rate determining step for SN1 reactions is the same as the rate determining step for E1 reactions.
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A load P is applied horizontally while the other end is fixed to a structure. where P = 185 N You have already examined the axial stresses inside the plates. In this problem, the bolted connections will be analyzed. Failure means that the pieces come apart because the bolts cannot hold the force. If two bolts are connecting the two plates, how much transverse force V must each bolt resist at each sheare joint?
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A freshwater jet boat takes in water through side vents and ejects it through a nozzle of diameter D = 75 mm; the jet speed is Vj. The drag on the boat is given by Fdrag =kV2, where V is the boat speed. Find an expression for the steady speed, V, in terms of water density rho, flow rate through the system of Q, constant k, and jet speed Vj. A jet speed Vj = 15 m=s produces a boat speed of V = 10 m=s. (a) Under these conditions, what is the new flow rate Q? (b) Find the value of the constant k. (c) What speed V will be produced if the jet speed is increased to Vj = 25 m=s? (d) What will be the new flow rate?
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Write a program with two inputs, current price and last month's price (both integers). Then, output a summary listing the price, the change since last month, and the estimated monthly mortgage computed as (currentPrice * 0.045) / 12. in coral
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The tangent function is defined as tan(theta) = sin(theta)/cos(theta). This expression can be evaluated to solve for the tangent as long as the magnitude of cos(theta) is no too near to 0. Assume that theta is given in degrees, and write the MATLAB statements to evaluate tan(theta) as long as the magnitude of cos(theta) is greater than or equal to 10e-2. If the magnitude of cos(theta) is less than 10e-2, write out an error message instead.
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A one-dimensional plane wall of thickness 2L=100mm experiences uniform thermal energy generation of q dot=1000 W/m^3 and is convectively cooled at x=+-50mm by an ambient fluid characterized by T infinity=20degreesC. If the steady-state temperature distribution within the wall is T(x)=a(L^2-x^2)+b where a=10 degrees C/m^2 and b=30 degrees C, what is the thermal conductivity of the wall? What is the value of the convection heat transfer coefficient, h?
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Calculate the magnitude of the force FB in the back muscles that is needed to support the upper body plus the box and compare this with his weight. The mass of the upper body is 55.0 kg and the mass of the box is 30.0 kg.
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Consider the general form of the Reynolds transport theorem (RTT) given by dBsys dt = d dt CV rhob dV + CS rhobV rn dA where V r is the velocity of the fluid relative to the control surface. Let Bsys be the mass m of a closed system of fluid particles. We know that for a system, dm/dt = 0 since no mass can enter or leave the system by definition. Use the given equation to derive the equation of conservation of mass for a control volume.
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A road has a crest curve, where the PVI station is a 71 35. The road transitions from a 2.1% grade to a -3.4% grade. The highest point of the curve is at station 74 10. What are the PVC and PVT stations
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Consider a subsonic engine inlet (i.e., a diffuser) with an inlet area of 1.5 m and exit-to-inlet area ratio of 1.44. Air enters the diffuser flowing at 5 kg/s with a static pressure of 0.350 bar and a velocity of 110 m/s. The gases exit the diffuser at a static pressure of 0.375 bar and a velocity of 80 m/s. Assume that the ambient (external) pressure on the walls of the diffuser is 0.340 bar. (a) For these conditions, what is the force (in units of lbf and N) transmitted to the structure holding the diffuser? Provide both the direction and magnitude of the force and use a picture to help present your answer. (b) Based solely on your results, comment on whether the force acting on the diffuser would help speed up or slow down a vehicle that used this diffuser as part of a jet propulsion system.
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Write a program to calculate the property tax. Property tax is calculated on 92% of the assessed value of the property. For example, if the assessed value is $200,00.00, the property tax is on 184,000.00. Assume that the property tax rate is $1.05 for each $100 of the assessed value. Your program should prompt the user to enter the assessed value of the property. Store the output in a file in the following format. (Here is a sample output.
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In a typical transmission line, the current I is very small and the voltage V is very large. A unit length of the line has resistance R. For a power line that supplies power to 10 000 households, we can conclude that:a) ????V < ????^2 Rb) ????^2 R = 0c) ????V = ????^2 Rd) ????V > I^2 Re) ???? = V/R
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A closed tank contains ethyl alcohol to a depth of 66 ft. Air at a pressure of 23 psi fills the gap at the top of the tank. Determine the pressure at a closed valve attached to the tank 10 ft above its bottom
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4.In which of these areas is GPS least reliable in giving you an accurateroute?A. major highwaysB. city streetsC. roads that are under constructionD. suburban roads
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Two sections of a pressure vessel are to be held together by 5/8 in-11 UNC grade 5 bolts. You are told that the length of the bolts is 1.5 in, the length of the threaded portion of the bolts is 0.75 in, and that their elastic modulus is E=30 Mpsi. The total load on the joint is 36 kip and the stiffness of the members is given as km=8.95 Mlbf/in. What is the minimum number of bolts that should be used to guard against excess proof strength with a factor of safety of np=1.2? Be sure to make an estimate for the preload.
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Water at 60F passes through 0.75-in-internal diameter copper tubes at a rate of 1.2 lbm/s. Determine the pumping power per ft of pipe length required to maintain this flow at the specified rate.The density and dynamic viscosity of water at 70F are rho = 62.30 lbm/ft^3 and = 6.556 x 10^-4 lbm/ft*s. The roughness of copper tubing is 5 x 10^-6 ft.The pumping power per ft of pipe length required to maintain this flow at the specified rate = _________ W (per ft length)
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What are the three most common types of relearn procedures?
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A three-phase, 600 MVA, 13.8KV AC generator has a synchronous reactance of 2.0 per unit. The generator is connected to a system for which the specified bases are 100MVA and 345KV. a) Find the per-unit value of the generator synchronous reactance on the specified bases. b) Find the ohmic value of the synchronous reactance. Problem 4 A single-phase source is connected to an electrical load. The load
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A cylindrical specimen of some metal alloy 11.2 mm (0.4409 in.) in diameter is stressed elastically in tension. A force of 15600 N (3507 lbf) produces a reduction in specimen diameter of 5 10-3 mm (1.969 10-4 in.). Compute Poisson's ratio for this material if its elastic modulus is 100 GPa (14.5 106 psi).
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A 3-kg block rests on top of a 2-kg block supported by, but not attached to, a spring of constant 40 N/m. The upper block is suddenly removed. Determine (a) the maximum speed reached by the 2-kg block, (b) the maximum height reached by the 2-kg block.
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George and Ellen Rottweiler encourage their adult daughter Guinevere to break her engagement and continue living in their home, saying, "You're so bright and attractive; you can find a better guy than this." A family systems theorist would term this as a(n) ________.
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A fire hose nozzle has a diameter of 1.125 in. According to some fire codes, the nozzle must be capable of delivering at least 250 gal/min. If the nozzle is attached to a 3-in.-diameter hose, what pressure must be maintained just upstream of the nozzle to deliver this flowrate?
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In a CNC milling machine, the axis corresponding to the feed rate uses a dc servomotor as the drive unit and a rotary encoder as the feedback sensing device. The motor is geared to a leadscrew with a 10:1 reduction (10 turns of the motor for each turn of the leadscrew). If the leadscrew pitch is 6 mm, and the encoder emits 60 pulses per revolution, determine (a) the rotational speed of the motor and (b) pulse rate of the encoder to achieve a feed rate of 300 mm/min.
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