Answer:
Hello your question lacks some vital parts here is the complete question
Determine Er(10) for this material (in Mpa) If the initial stress level was 2.76 Mpa (400psi) which dropped to 1.72 Mpa(250psi) after 60s
Answer: Er(10) for the material = 2.55 / 0.69 = 3.695 ≈ 3.70 Mpa
Explanation:
The equation of stress decay for viscoelastic polymers
equation 1
t = elapsed time = 60s
T = relaxation time
input the given values into the equation
1.72 = 2.76 exp ( -
exp ( - 60/T ) = 1.72/2.76 therefore T = 126.87S
Considering 10s for t
taking Ln of both sides of the equation
Ln
therefore = 370 psi
To determine the Er(10) for the material in (Mpa) we apply the relaxation modulus equation
Er(t) =
where Eo = strain level = 0.69
Er(t) = E(10)
= 2.55 Mpa
input this variables into equation
Er(10) for the material = 2.55 / 0.69 = 3.695 ≈ 3.70 Mpa
To develop the problem it is necessary to apply the concepts related to the ideal gas law, mass flow rate and total enthalpy.
The gas ideal law is given as,
Where,
P = Pressure
V = Volume
m = mass
R = Gas Constant
T = Temperature
Our data are given by
Note that the pressure to 38°C is 0.06626 bar
PART A) Using the ideal gas equation to calculate the mass flow,
Therfore the mass flow rate at which water condenses, then
Re-arrange to find
PART B) Enthalpy is given by definition as,
Where,
= Enthalpy of dry air
= Enthalpy of water vapor
Replacing with our values we have that
In the conversion system 1 ton is equal to 210kJ / min
The cooling requeriment in tons of cooling is 437.2.
<h2>Question:</h2>
Which of the following is NOT a problem associated with surface mining?
<h2>Answer:</h2>
<u>Oil</u><u> </u><u>spills</u><u> </u>
<h2>
<u>#CARRYONLEARNING</u><u> </u></h2><h2>
<u>#STUDYWELL</u><u> </u></h2>
Answer: The black diamonds which appear every 19 3/16” on metal tape measures are for spacing I-beam “timbers”.
Explanation:
Answer:A. 40% B.50% C. 60% Od 70%
Explanation:A. True B. False