Problem 4.084 SI A rigid copper tank, initially containing 1.5 m3 of air at 295 K, 4 bar, is connected by a valve to a large supply line carrying air at 295 K, 15 bar. The valve is opened only as long as required to fill the tank with air to a pressure of 15 bar. Finally, the air in the tank is at 320 K. The copper tank, which has a mass of 20 kg, is at the same temperature as the air in the tank, initially and finally. The specific heat of the copper is c = 0.385 kJ/kg · K. Assuming ideal gas behavior for the air, determine: (a) the initial and final mass of air within the tank, each in kg, and (b) the heat transfer to the air and copper tank from the surroundings, in kJ, ignoring kinetic and potential energy effects.

What are the microstructural differences between thermoset s and vulcanized elastomers? Explain the different mechanical behavior of each.

I know I have to say something about "density of chemical bonding" but I am not quite sure what.

In a annealing there are different stages, can explain the stages and show in a plot the ductility overtime

discussion and conclusion for the thermal conductivity of solids Lab for the thermodynamics course

The value of f depends on two independent variables x and y as defined below:

f(x,y)=x2+y2−x+3cos(x)sin(y)

Function f has a minimum in the neighborhood of the origin (i.e. [0 0]). Find x and y which minimize f.

Note: You are not allowed to use MATLAB built-in functions for optimization. Follow the logic of the derivative test:

The minimum of f occurs where:

∂f∂x=0∂f∂y=0

At approximately what temperature (in Kelvin) would a specimen of an alloy have to be carburized for 2.6 h to produce the same diffusion result as at 880°C for 13 h? Assume that values for D₀ and Q_d are 1.3 × 10^-4 m²/s and 139 kJ/mol, respectively.

Q1. Explain the advantages and disadvantages of using the Zygo versus using the Mahr profilometer.

Q2.Would you use the Zygo or the Mahr in an industrial setting and why?

Two samples of a low hardness steel were tested using a Rockwell C hardness tester and the Rockwell B scale at the same lab on the same day . The difference between the average hardness of the two samples was 0.5 Rockwell C. Do you think there is a significant difference in the hardness? Justify your answer. Hint: Use the specification!!

Below is a model response solution. Rewrite this solution in one line using a correct notation that includes Heaviside functions.

x(t) = e?2t sin(3.46t) t < 3s

x(t) = e?2t sin(3.46t) + 0.2e?2(t?3) sin(3.46(t ? 3)) 3s ? t < 5s

x(t) = e?2t sin(3.46t) + 0.2e?2(t?3) sin(3.46(t ? 3))+1 + 1 e?2(t?5)cos(3.46(t?5)?0.52) t?5s 16 13.86

An austenitized 70 mm diameter 4340 steel bar is quenched in agitated H2O. Predict what the Rockwell C hardness of the bar will be at (a) its surface, (b) 3/4-R, (c) midway between its surface and center and (d) at its center

(a) S: _53_____                      (b) 3/4R: __52_____ (c) MR: __52_____      (d)

C: __51____

Please show work

Assuming the elastic solution for the stresses near a crack tip is valid in the case of small-scale yielding, determine r_p(q) for Mode I and Mode II  in plane stress and plane strain. Plot a nondimensional r_p(q), ( r_p/ r_p(Irwin)) in the vicinity of the crack tip for several different values of Poisson's ratio.

For an ideal vapor-compression heat pump cycle, refrigerant 134a is used to provide 35 kW of heat to a building. Saturated vapor enters the compressor at 1.6 bar and saturated liquid exits the condenser which operates at 8 bar. What is (a) the mass flow rate of the refrigerant, and (b) the COP?

Thermodynamics

1. The answer is -12.31 can someone please explain how we get that.

A pump steadily delivers 9.7 kg/s of water at the conditions given below. Calculate the pump power (hp).

The rate of heat transfer from the pump to the surroundings is Q = 1.7 kW.

There are no changes in kinetic or potential energy.

Pump Inlet Temperature = 50^oC

Pump Inlet Pressure = 115 kPa

Pump Exit Temperature = 50^oC

Pump Exit Pressure = 877 kPa

2.

A pump steadily delivers 9.7 kg/s of water at the conditions given below. Calculate the pump power (hp).

The rate of heat transfer from the pump to the surroundings is Q = 1.7 kW.

There are no changes in kinetic or potential energy.

Pump Inlet Temperature = 50^oC

Pump Inlet Pressure = 115 kPa

Pump Exit Temperature = 50^oC

Pump Exit Pressure = 877 kPa

3.

can someone please explain how we get the answer -40.45

A pump steadily delivers 7.89 kg/s of water at the conditions given below. Calculate the pump power (hp).

The rate of heat transfer from the pump to the surroundings is Q = 1.42 kW.

There are no changes in kinetic or potential energy.

Pump Inlet Temperature = 50^oC

Pump Inlet Pressure = 1.05 MPa

Pump Exit Temperature = 50^oC

Pump Exit Pressure = 4.65 MPa

which type of gear material used for making a gear using in jurk?