Sketch constant preassure curve in T-s diagram.
In: Mechanical Engineering
A metal bar, initially at 2000K, is placed in a large tank of water at room temperature. Tank is well isolated from the environment. Between the moment bar was placed in the water and the moment when bar and water reached equilibrium, did the entropy of the metal bar increased, decreased, or remained the same? Explain.
In: Mechanical Engineering
Process X is internally reversible from state 1 to 2. Process Y is internally irreversible between same states 1 to 2. What can you say about the change in entropy of the system during process X and Y? Is one larger than the other or are they the same? Explain.
In: Mechanical Engineering
A 1-mm diameter sphere (density=7900 kg/m3) is dropped into a tank of oil (density=900 kg/m3). The sphere develops a terminal speed of 0.25 cm/s, what is the oil's viscosity? You may assume a small Reynolds number. Show your work.
In: Mechanical Engineering
4. Explain why the energy efficiency in the case of ideal quenching is lower than energy efficiency in the regime of super-ideal quenching?
In: Mechanical Engineering
In: Mechanical Engineering
A composite of Al2O3 particles in an epoxy matrix contains 10 wt.% Al2O3. What are the upper and lower bounds on the elastic modulus of the composite? Data: ρAl2O3 = 3.95 g/cm3 , EAl2O3 = 300 GPa, ρepoxy = 2.0 g/cm3 , and Eepoxy = 500 MPa.
In: Mechanical Engineering
A stock steel spur pinion has a diametral pitch of pd=8 teeth/in, a 1.5 in. face, 26 full-depth teeth, and a pressure angle of Φ = 20°. If the pinion is driven against a 55-tooth steel gear at 1200 RPM by a 7 hp electric motor, determine the bending stresses and surface stresses in the pinion.
In: Mechanical Engineering
how could mechanical engineering improve plastic recycle?
In: Mechanical Engineering
A short and hollow cylindrical bar, having an outer diameter of
4.00 in and an inner diameter of 7 in, is
subjected to two simultaneous loads - an axial compressive force of
75,100 lb. and a torsional moment of
20,100 lb • in.
You are required to create two-dimensional (2D) and
three-dimensional (3D) stress elements for two stress
states on the outer and inner surfaces of the bar to in-plane and
out-of-plane stresses, respectively and then
draw the 2D and 3D Mohr's circles for these two cases.
In: Mechanical Engineering
In: Mechanical Engineering
Engineering report writing on autoclave (sterilizer) machine breakdown which occurs more often due to hard water/untreated water. The factors which leads to that and the solution to the problem. Recommendation and Summation to be included. Write 3 to 4 A4 pages.
In: Mechanical Engineering
A convergent–divergent nozzle with an exit area to throat area ratio of 3 is supplied with air from a reservoir in which the pressure is 350 kPa. The air from the nozzle is discharged into another large reservoir. It is found that the flow leaving the nozzle exit is directed inward at an angle of 4° to the nozzle centerline. The velocity on the nozzle exit plane is supersonic. What is the pressure in the second reservoir?
In: Mechanical Engineering
In transonic wind tunnel testing, the small area decrease caused by placing the model in the test section, i.e., by the model blockage, can cause relatively large changes in the flow in the test section. To illustrate this effect, consider a tunnel that has an empty test section Mach number of 1.08. The test section has an area of 1 m2 and the stagnation temperature of the air flowing through the test section is 25°C. If a model with a cross-sectional area of 0.005 m2 is placed in this test section,find the percentage change in test section velocity. Assume one-dimensional isentropic flow.
In: Mechanical Engineering