Engineering

Consider a Venturi with a throat-to-inlet area ratio of 0.8, mounted on the side of an airplane fuselage. The airplane is in flight at standard sea level. If the static pressure at the throat is 2100 lb/ft, calculate the velocity of the airplane. Note that standard sea-level density and pressure are 1.23 kg/m (0.002377 slug/ft) and 1.01 x 10 N/m2 (2116lb/ft), respectively.
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Describe briefly the main advantages offered by satellite communications. Explain what is meant by a distance-insensitive communications system.
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A sand has a natural water content of 5% and bulk unit weight of 18.0 kN/m3. The void ratios corresponding to the densest and loosest state of this soil are 0.51 and 0.87. Find the relative density and degree of saturation.
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A heat engine does 210 J of work per cycle while exhausting 440 J of waste heat. Part A What is the engine's thermal efficiency? Express your answer using two significant figures.
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A rectangular block of material with shear modulus G= 620 MPa is fixed to rigid plates at its top and bottom surfaces. Thelower plate remains fixed while the upper plate is subjected to a horizontal force, P. If the top plate displaces 2 mm horizontally, determine:a. the average shear strain in the material b. the force P exerted on the upper plate.
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To use Allowable Stress Design to calculate required dimensions using a specified factor of safety. A structural element that carries a load must be designed so that it can support the load safely. There are several reasons why an element may fail at loads that are less than the theoretical limit. For example, material properties may not exactly equal the reference values used in the design. The actual loading may differ from the design loading. The exact dimensions of the member may be different from the nominal values. These scenarios, and others, make it important to design structural members so that the expected load is less than the expected load that would make the member fail. One method of doing this uses a factor of safety. The allowed load Fallow can be related to the load that causes failure, Ffail, using a constant called the factor of safety, F.S.=FfailFallow, which should be larger than 1. For preliminary analysis, the stresses that are developed are assumed to be constant, so that the load and the stress are related by N=A or V=A, where A is the area subjected to the load. An anchor rod with a circular head supports a load Fallow = 11 kN by bearing on the surface of a plate and passing through a hole with diameter h = 2.6 cm. One way the anchor could break is by the rod failing in tension. What is the minimum required diameter of the rod if the factor of safety for tension failure is F.S. = 1.6, given that the material fails in tension at fail = 60 MPa? Assume a uniform stress distribution.
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A clay sample has a wet mass of 417 g, a volume of 276 cm3, and a specific gravity of 2.70. When oven dried, the mass becomes 225 g. Calculate: a) The water content, b) the void ratio, and c) the degree of saturation.
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The electronics aboard a certain sailboat consume 50 W whenoperated from 12.6-V source. If a certain fully charged deep-cyclelead acid storage battery is rated for 12.6 V and 100 ampere hours,for how many hours can the electronics be operated from the batterywithout recharging. (The ampere-hour rating of the battery is theoperating time to discharge the battery multiplied by the current.)How much energy in Kilowatt hours is initially stored in thebattery? If the battery costs $75 and has a life 0f 300charge-discharge cycle, what is the cost of the energy in dollarsper kilowatt hour? Neglect the cost of recharging the battery.
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Given the vector current density J = 10rho2zarho 4rho cos2 a mA/m2: (a) find the current density at P(rho = 3, = 30, z = 2); (b) determine the total current flowing outward through the circular band rho = 3, 0 < < 2, 2 < z < 2.8
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an ideal otto cycle has a compression ratio of 8. at the begining of the compression process, air is at 95 kpa and 27 c, and 750kj/kg of heat is transferred to air during the constant volume heat addition process Taking into account the variation of specific heats with temperature, determine (a) the pressure and temperature at the end of the heataddition process, (b) the net work output, c) the thermal efficiency, and (d) the mean effective pressure for the cycle.
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Two transistors, fabricated with the same technology but having different junction areas, when operated at a base-emitter voltage of 0.75 V, have collector currents of 0.4 mA and 2 mA. Find IS for each device. What are the relative junction areas?
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The volume of air in one beach ball is 288 in 3. What is the volume of air in a ball whose radius is 3 inches greater than the first beach ball?
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Find support reactions at A and B and then calculate the axial force N, shear force V, and bending moment M at mid-span of AB. Let L 5 4 m, q0 5 160 N/m, P 5 200 N, and M0 5 ? 380 N m.
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Problem 1 (10 points) In the first homework you were instructed to design the mechanical components of an oscillating compact disc reader. Since you did such a good job in your design, the company decided to work with you in their latest Blue-ray readers, as well. However, this time the task is that once the user hits eject button,
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What are the effects of applying an additional layer of insulation to a cylindrical pipe or a spherical shell?
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An interest buydown program offers to reduce interest rates by 4% from the base rate. Suppose the base rate for a loan of $8000 is 8% for 10 years. What is the monthly payment before and after the buydown? In this case, use monthly compounding, that is, the term is 120 payment periods, and the interest per month is 0.667% before and 0.333% after the buydown.
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Which of the following would require the filing of an EIS? a. expansion of an airport in a national park b. allowing snowmobiles in a national park c. erecting a research telescope facility in a national park d. All of the above would require an EIS.
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a. To measure the water current in an ocean, a marker is dropped onto it. Determine if the trajectory traced by the drifting marker forms a streamline, streakline, or pathline.b. To learn more about the flow, a large number of similar markers are released at the same point in space in quick succession. Determine if the line connecting these markers at a later instant forms a streamline, streakline, or pathline.
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A "scale" is constructed with a 4-ft-long cord and the 10-lb block D. The cord is fixed to a pin at A and passes over two small pulleys at B and C. Determine the weight of the suspended block E if the system is in equilibrium when s= 1.5 ft.
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A closed, rigid tank is lled with a gas modeled as an ideal gas, initially at 27C and a gage pressure of 300 kPa. The gas is heated, and the gage pressure at the nal state is 367 kPa. Determine the nal temperature, in C. The local atmospheric pressure is 1 atm.
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Ammonia gas is diffusing at a constant rate through a layer of stagnant air 1 mm thick. Conditions are such that the gas contains 50 per cent by volume ammonia at one boundary of the stagnant layer. The ammonia diffusing to the other boundary is quickly absorbed and the concentration is negligible at that plane. The temperature is 295 K and the pressure atmospheric, and under these conditions the diffusivity of ammonia in air is 1.8 x 10~5 m2/s. Estimate the rate of diffusion of ammonia through the layer.
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what is the displacement of the ball at t=4 seconds
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Water is flowing in a 3 cm diameter garden hose at a rate of 25 L/min. A 20 cm long nozzle is attached to the hose which decreases the diameter to 1.2 cm. The magnitude of the acceleration of a fluid particle moving down the centerline of the nozzle is
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A Sampling of 409 motor Shafts from a very large production Batch shows a sample standard deviation in Diameter of 0.021 mm with a sample mean of 9.251 mm Estimate the mean diameter of the entire batch at a %95 level of confidences?
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