Discuss the testing procedures for a fibre composite material, showing all parties involved, from the beginning until obtaining final test report. Discuss also the importance and need of obtaining such test results and not to rely solely on the results of theoretical evaluation. Support your discussion with appropriate literature

Air (cp = 1.0 kJ/kgK) enters an air conditioning system at 40C with a mass flow rate of 1.5 kg/s. The air is cooled by exchanging heat with a stream of R-134a refrigerant that enters the heat exchanger at -8C and 20% quality, and exits with 100% quality. If 25 kW of heat is transferred out of the air, determine: (40 pts) i) Mass flowrate of R-134a (kg/hr) ii) Exit temperature of air (C) iii) Exit pressure of R-134a (kPa)

3. A CNC Lathe is controlled by a 151 step motor which is used to drive a lead screw with 0.25 inch pitch.

(i) What is the precision or minimum distance a carriage on the lead screw can be moved.

4 Decimals, Unit: inch

(ii) To move a distance of 4.5 inches how many pulses are transmitted to the motor.

(iii) If the specification is to move the carriage at the rate of 2.2 inches/minute at what frequency should the pulses be transmitted.

Unit: Hertz

8. Consider an airplane whose takeoff speed is 220 km/h and that takes 15 s to take off at sea level. For an airport at an elevation of 1600 m (such as Denver), determine (a) the takeoff speed, (b) the takeoff time, and (c) the addition al runway length required for this airplane. Assume constant acceleration for both cases.

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5.

Define inorganic glass ?

Explain main glass formers, conditional glass formers,

intermediate oxides, and network modifiers? In a viscosity versus temperature profile,

can you please define strain point, annealing point, glass transition temperature, softening

point, and working p

oint

?

5. Consider an airplane with wingspan 40 ft, wing area 250 ft2 , and weight 12,000 lb. Assume that the Oswald efficiency factor is 0.9. The airplane is flying at a velocity of 250 mph at a standard altitude of 5000 ft. Calculate the airplane drag due to lift.

3. A jet aircraft has a drag polar CD = CD,0 + CL 2 /(?e?) = 0.02 + 0.04 CL 2 and wing area 500 m2 . Its initial weight is 3,000,000 N, which includes the fuel weight 1,000,000 N. The thrust specific fuel consumption is 0.9 (N of fuel) / (N of thrust ·hour). Find the maximum endurance of this aircraft.

This is a numerical methods question using MATLAB.

Which of the following code snippets finds the forward difference estimate of the derivative at each of the x values. Assume x and y have been previously defined, for example as

y=[10,20,25, 27.5, 30];
x = [0.3,0.5, 0.8, 0.9, 1];

(d is the derivative variable name)

Although not necessarily so, there may be more than one correct answer.

A wall is constructed of two layers of 2-cm-thick sheetrock (k = 0.17 W/m·K) separated by 16 cm by wood studs (k = 0.11 W/m·K) whose width is 5 cm. The studs are placed vertically 55 cm apart, and the space between them is filled with stagnant air (16 by 55 cm) as insulation (k = 0.026 W/m·K). Pay attention to the measurements!

The house is maintained at 20°C and the ambient temperature outside is ?9°C. Taking the heat transfer coefficients at the inner and outer surfaces of the house to be 8.3 and 34 W/m²·K, respectively, determine the thermal resistance of the wall in C/W considering arepresentative section (1m x 0.60 m) of the wall to three significant digits. That is from stud end to the other stud end...so a single stud in your section..see plan view below and an example to the right without the sheetrock.

Q] The historical actual sales of an item purchased by a factory is given below. What would have been the forecast had the manager a) used 3 period moving average to make the forecast in the past, and b) used exponential smoothing with alpha=0.2 to make the forecast in the past. Show all calculations. PLEASE PROVIDE TABULATED EXCEL CALCULATIONS.

Sub: Material Science

For a bolted assembly with six bolts, the stiffness of each bolt is kb = 4 Mlbf/in and the stiffness of the members is km = 16 Mlbf/in per bolt. A fluctuating external load applied to the entire joint cycles between 20,000 lbf and 40,000 lbf. Assume the load is equally distributed to all the bolts. It has been determined to use 3/8 in - 16 UNC grade 8 bolts with rolled threads. Assume the bolts are preloaded to 75% of the proof load.
(a) Determine the alternating stress and mean stress carried by a bolt.
(b) Determine the fatigue factor of safety for infinite life, using the Goodman criterion and a load line that assumes the preload is carefully applied and will not vary during operation.

If the valve face and valve seat do not contact each other evenly after reconditioning---. a. regrind the value with the same stone b regrind the seats with stones of different angles c. knurl the valve guide d. none of the above

6-A frame ^UF was moved along its own n-axis a distance of 5 units, then rotated about its o-axis an angle of 60⁰ , followed by a rotation of 60⁰ about the z-axis, then translated about its a-axis for 3 units, and finally rotated 45⁰ about the x-axis. Calculate the total transformation performed.

You decide to design a heating element using a piece of polished copper wire, 10mm in diameter with an emissivity of 0.08. It will maintain a constant surface temperature of 325°C when immersed inwater.

a. How did we know to apply film boiling to this scenario? (Hint–look at the boiling curve.)

b. What is the rate of heat transfer from the wire to the water per unit length ofwire?

Hint: The corrected total heat transfer due to a vapor film impeding radiation is: q(total) = q(film) + 3/4q(radiation)

Calculate the takt given the following information: ? Two shifts at 8 hours each shift ? Two 10-minute breaks per shift ? 25 minute lunchtime per shift ? There are a total of 8 holidays per year ? Normal work schedule is 5 days per week (Monday-Friday) ? Customer contract calls for 450,000 units/year (contractual agreement) You must show ALL your work/calculations in order to get full credit!