Answer: True
Explanation:
Permanent molds do not collapse, unlike expendable molds so the mold must be opened before appreciable cooling contraction occurs in order to prevent cracks from developing in the casting.
The metal casting becomes solid inside the mold after it has been poured. But during the process of manufacture, before the would cools any further, they usually remove the metal cast in order to stop excess contractions of the solid metal casting in the mold. This is done to prevent prevent cracks from developing in the casting since permanent mold do not collapse.
Answer:
conditional instability (Γd > Γe > Γw)
Explanation:
Given;
dry adiabatic rate, Γd = 10ºC/1000 meters
wet adiabatic rate, Γw= 6.5ºC/1000 meters
environmental lapse rate, Γe = 7.8ºC/1000 meters
Stability of the atmosphere can be described as Absolute stability, Absolute instability or conditional instability.
Conditions for Absolute stability:
Γd > Γw > Γe
Conditions for Absolute instability:
Γe > Γd > Γw
Conditions for conditional instability:
Γd > Γe > Γw
Thus, conditional instability satisfies the given values of the atmospheric condition: Γd (10) > Γe (7.8) > Γw (6.5)
Answer:
Part a : The SI unit of σ is Pascal.
Part b : The pressure is 414.28 psi.
Explanation:
Part a
The equation is given as
As per the dimensional analysis
![M=[N-m]\\y=[m]\\l=[m^4]](https://tex.z-dn.net/?f=M%3D%5BN-m%5D%5C%5Cy%3D%5Bm%5D%5C%5Cl%3D%5Bm%5E4%5D)
So the equation becomes
![\sigma =\frac{[N-m][m]}{[m^4]}\\\sigma =\frac{[N][m^2]}{[m^4]}\\\sigma =\frac{[N]}{[m^{4-2}]}\\\sigma =\frac{[N]}{[m^{2}]}\\](https://tex.z-dn.net/?f=%5Csigma%20%3D%5Cfrac%7B%5BN-m%5D%5Bm%5D%7D%7B%5Bm%5E4%5D%7D%5C%5C%5Csigma%20%3D%5Cfrac%7B%5BN%5D%5Bm%5E2%5D%7D%7B%5Bm%5E4%5D%7D%5C%5C%5Csigma%20%3D%5Cfrac%7B%5BN%5D%7D%7B%5Bm%5E%7B4-2%7D%5D%7D%5C%5C%5Csigma%20%3D%5Cfrac%7B%5BN%5D%7D%7B%5Bm%5E%7B2%7D%5D%7D%5C%5C)
As the dimensions are of pressure so the SI unit of σ is Pascal.
Part b
Pressure in US customary base units is given in psi so
So
So the pressure is 414.28 psi.
The fumes from are eztremeynakd haczorurduz cememnt
