Engineering Questions

Molybdenum (Mo) has a BCC crystal structure, an atomic radius of 0.1363 nm, and an atomic weight of 95.94 g/mol. Compute and compare its theoretical density with the experimental value found inside the front cover of the textbook.
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If pure oxygen is fed in excess by 25%, what would the fractional conversion of methane be for the final concentration of CO2 in the outlet stream, in mole percent, to be 10%?
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In a balanced Y-Y three-phase circuit 120 10 Van    V rms. The load impedance per phase is 20 15 ZZ j L Y    . Determine the load voltages and line currents. Consider a positive sequence for the three-phase circuit.
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An A-26C aircraft has 2 piston engines driving propellers. It is climbing at a flight-path angle of 10 degrees. The aircraft weighs 32,000 pounds (142,343 Newtons). For a steady climb, EACH engine must overcome how much weight in addition to the drag of the airplane?
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The mechanical advantage of a screw is always ____________________ than/to 1. Question 5 options: less, greater, equal, none of the above
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Argon is compressed in a polytropic process with n = 1.2 from 120 kPa and 10°C to 850 kPa in a piston–cylinder device. Determine the work produced and heat transferred
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10. Aluminum-lithium (Al-Li) alloys have been developed by the aircraft industry to reduce the weight and improve the performance of this aircraft. A commercial aircraft skin material having a density of 2.47g/cm3 is desired. Compute the concentration of Li (wt%) that is required.
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Air is compressed adiabatically from p1 1 bar, T1 300 K to p2 15 bar, v2 0.1227 m3 /kg. The air is then cooled at constant volume to T3 300 K. Assuming ideal gas behavior, and ignoring kinetic and potential energy effects, calculate the work for the first process and the heat transfer for the second process, each in kJ per kg of air. Solve the problem each of two ways:
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The Compartments of these tanks are closed and filled with air.Gage A read 207KPa. Gage B registers a vacuum of 254mm of mercury.What will gage C read if it is connected to compartment 1 butinside compartment 2? Barometric pressure is 101 KPa, absolute. Hint: Changes pressure Gage B from mm of mercury to KPa. 254mm of mercury is 33.86KPa.
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Technician A says that some multiplexing systems use a data bus that consist of a twisted pair of wires. Technician B says that some multiplexing systems use a data bus that consists of a single wire. Who is correct?
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The lead of the threaded shaft of the C-clamp is 0.05 in., and the mean radius of the thread is r = 0.15 in. Assume mus = 0.18. What couple must be applied to the shaft to exert a 30-lb force on the clamped object?
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Smoke rises from a chimney on a day with variable winds and produces a visible pattern. Does this pattern represent a pathline or a streakline? Under what conditions might the pathline and streakline be the same?
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Explain why test-first development helps the programmer to develop a better understanding of the system requirements. What are the potential difficulties with test-first development?
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Some designers suggest that speech recognition should be used in a telephone menu system. This would allow users to interact with the system by speaking instead of pressing buttons on the dial pad. Give two arguments for and three arguments against the proposal.
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A cylindrical specimen of this alloy 12.7 mm in diameter and 250 mm long is stressed in tension and found to elongate 7.6 mm. On the basis of the information given, is it possible to compute the magnitude of the load that is necessary to produce this change in length? If so, calculate the load. If not, explain why.
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Technician A says damage can occur to solid-state circuitry if the charging voltage is allowed to get too high. Technician B says damage can occur if the vehicle is allowed to run with the battery disconnected. Who is correct?
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One type of illumination system consists of rows of strip fluorescents and a ceiling that will transmit light. For this system to be efficient, the surfaces above the luminous ceiling must be ____.
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On a large lake without waves, how far from shore is a sailboat when the top of its 7-m mast disappears from the view of a person whose eye height is 1.7 m above the water’s edge?Express your answer to three significant figures and include appropriate units.
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For a 2 Vpp signal that fits within the ADC’s input range, find the SQNR for: a) an 8-bit ADC with an input range of 1V to 6V b) a 9-bit ADC with an input range of 0V to 4V
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Why is the thermal efficiency of the auto cycle higher than Diesel engine? What is thereason for increasing use of Diesel cycle instead of Otto cycle?
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A large piece of equipment in power plants (coal, petroleum, nuclear and geothermal) that converts mechanical energy into an electric current is called a _____________.
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For methyl chloride at 100°C the second and third virial coefficients are: B = −242.5 cm 3 ·mol −1 C = 25,200 cm 6 ·mol −2 Calculate the work of mechanically reversible, isothermal compression of 1 mol of methyl chloride from 1 bar to 55 bar at 100°C. Base calculations on the following forms of the virial equation: (a) Z = 1 + B __ V + C ___ V 2 (b) Z = 1 + B′P + C′ P 2 where B′ = B ___ RT and C′= C − B 2 _____ ( RT ) 2 Why don’t both equations give exactly the same result?
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Air in a spring-loaded piston/cylinder setup has a pressure that is linear with volume, P = A + BV. With an initial state of P = 150 kPa, V = 1 L and a final state of 800 kPa, V = 1.5 L, it is similar to the setup in Problem 3.48. Find the work done by the air. 3.54 Helium gas expands from 125 kPa, 350 K and 0.25 m3 to 100 kPa in a polytropic process with n = 1.667. How much work does it give out?
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What are the mechanical properties of a geotextile that are of most importance when using it as a separator in an unpaved road situation with only stone base above it and relatively firm soil below it?
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