Engineering

find the first principle derivative for 3/x with respect to x.
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Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at 2208C with a mass flow rate of 1.2 kg/s. Refrigerant exits at 7 bar, 708C. Changes in kinetic and potential energy from inlet to exit can be ignored. Determine (a) the volumetric flow rates at the inlet and exit, each in m3 /s, and (b) the power input to the compressor, in kW.'
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Show that a short-circuited losalesa transmission line looks at its input end as an inductor or a capacitor. This property is used in integrated microwave circuits to simulate a capacitor or an traductor.
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The value of universal gas constant is same for all gases?a) yesb)No
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A balanced three-phase inductive load is supplied in steady state by a balanced three-phase voltage source with a phase voltage of 120 V rms. The load draws a total of 10 kW at a power factor of 0.85 (lagging). Calculate the rms value of the phase currents and the magnitude of the per-phase load impedance. Draw a phasor diagram showing all tlme voltages and currents.
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Car B is traveling a distance dd ahead of car A. Both cars are traveling at 60 ft/s when the driver of B suddenly applies the brakes, causing his car to decelerate at ft/s^2. It takes the driver of car A 0.75 s to react (this is the normal reaction time for drivers). When he applies his brakes, he decelerates at 18 ft/s^2.Required:Determine the minimum distance d between the cars so as to avoid a collision.
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An ideal fluid flows through a pipe made of two sections with diameters of 1.0 and 3.0 inches, respectively. The speed of the fluid flow through the 3.0-inch section will be what factor times that through the 1.0-inch section
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A resistivity meter is measured in
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Your boss is given a new cylindrical aluminum part to be sand cast. The part is adisk 50 cm in diameter and 20 cm thick to be cast of pure aluminum in a closedmold system containing a gating system and riser volume that is 50% of the moldcavity volume. Assume that a superheat of 100C is used and that the aluminumproperties are as follows: Melting temperature of aluminum = 660C Latent heat of fusion = 389.3 J/g density Density = 2.70 g/cm3 Specific heat = 0.88 J/g-C. Assume the specific heat has the same value forsolid and molten aluminum.Q1:Compute the amount of heat (in MJ) that must be added to the metal to heat it to the pouring temperature, starting from a room temperature of 25C.Q2: Assume the same part in Q2 is being made with the same method. Based upon past experience when poured from the same temperature, the mold constant for sand casting an aluminum part was found to be 5 min/cm2. Determine the total solidification time (in minutes) for the part.Q3:Assume that the sand mold downsprue is 25 cm long and the cross-sectional area at the base is 2.5 cm2. The downsprue feeds a horizontal runner leading into a mold cavity. Assume also that the part has the same dimensions as described in Question 22 and that the volumetric contraction for the cast metal in the mold is 4.3%. Finally, assume that using the current superheat, it takes 28 seconds before solidification begins. What is the mold fill time (in seconds)?Q4: Will the mold fill before the start of freezing?Q5: Assume that a part with unknown dimensions uses a permanent mold casting process with a mold constant of 1 min/cm2 and that the part solidifies in 60 min. Calculate the dimensions (in cm) of an effective riser assuming that the riser is a cylinder with a height/diameter ratio H/D = 1 and that the riser will take 10% longer than the casting to solidify. H = D = ?
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For each function , sketch the Bode asymptotic magnitude and asymptotic phase plots. a. G(s)= 1/s(s+2)(s+4)b. G(s)= (s+5)/(s+2)(s+4)c. G(s)= (s+3)(s+5)/s(s+2)(s+4)
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Refrigerant-134a enters an adiabatic compressor at -30oC as a saturated vapor at a rate of 0.45 m3 /min and leaves at 900 kPa and 55oC. Determine (a) the power input to the compressor, (b) the isentropic efficiency of the compressor, and (c) the rate of exergy destruction and the second-law efficiency of the compressor. Take T0
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In the photograph above, the technician is doing what?
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4.65 A zener shunt regulator employs a 9.1-V zener diode for which VZ = 9.1 V at IZ = 9 mA, with rz = 40 and IZK= 0.5 mA. The available supply voltage of 15 V can varyas much as 10%. For this diode, what is the value of VZ0?For a nominal load resistance RL of 1 k and a nominal zenercurrent of 10 mA,what current must flow in the supply resistorR? For the nominal value of supply voltage, select a valuefor resistor R, specified to one significant digit, to provideat least that current. What nominal output voltage results?For a 10% change in the supply voltage, what variationin output voltage results? If the load current is reduced by50%, what increase in VO results? What is the smallest valueof load resistance that can be tolerated while maintainingregulation when the supply voltage is low? What is the lowestpossible output voltage that results? Calculate values for theline regulation and for the load regulation for this circuit usingthe numerical results obtained in this problem.
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Bi 3: Cho c cu cult (hnh 3.5) vi cc kch thc ng lAB = 0,5lAC = 0,1m. Khu 3 chu tc dng ca m men M3 = 500 N. C cu trng thi cn bng. Ti thi im khu 1 v tr 1 = 900 hy tnh p lc ti cc khp ng ti B, C v A.
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write a verilog description of the following combinational circuit using concurrent statements. Each gate has a 5-ns delay, excluding the inverter, which has a 2-ns delay. (consider the below circuit is a full module)
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What statement about the print() function is true?print() has a variable number of parameters.print() can have only one parameter.print() can be used to obtain values from the keyboard.print() does not automatically add a line break to the display.
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So I am going to do online school till I graduate and I have horrible internet. i only get about 3 quarters of each class I take so I miss most of it. WHAT DO I DO. my mom said she will never let me go back to a brick-and-mortar school.
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state two disadvantages and two advantages of a simple manometer.
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I am having trouble understanding how I got these wrong on my test. Is there something I am missing with xor?
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Discuss the organizational system that you believe would be the most effective for the safety officer in a medium-sized (100-200) manufacturing facility
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Calculate the number of 12 V batteries (capacity 120 Ah) needed to run a 3 kW DC motor that operates in 240 V. How many hours the motor will run with 20 of such batteries connected in series?
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A technician suspects that the EGR valve is closed. Which of the following would indicate a closed EGR valve?
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Why water parameters of Buriganga river vary between wet and dry seasons?Explain.
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Compute the minimum length of vertical curve that will provide 220 m stopping sight distance for a design speed of 110 km/h at the intersection of a -3.50% grade and a +2.70% grade.
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