Recent content by ScareCrow271828

Homework Statement What is constitutional undercooling? What are it's effects? Homework EquationsThe Attempt at a Solution Undercooling is when the liquid has a below freezing temperature. However konstituntial undercooling occurs during solidification when the liquid is brought to freezing...

Homework Statement From the phase diagram what can be said of the porosity, mechanical strength, and density of various materials in the diagram? Homework EquationsThe Attempt at a Solution I am having trouble finding research on the general properties of quartz, feldspaar, and clay mineral...

Thanks for the response. would dividing Q by Avogadro's number to get Q (kJ/atom) work? Boltzman constant is actually j/k*atom right? so the units would match then.

Homework Statement The activation energy of vacany formation in Zinc is 72kj per mole. What is the vacancy concentration at 687k Homework Equations Nv=Nexp(-Q/kt) N=p(Na/A) The Attempt at a Solution Seems very straight forward. Although I keep getting zero for the exponent term...

Does the question not ask to calculate it? Why can I not calculate E and V with a system of equations given the matrix and the c values? C11=(E(1+v))/((1+v)(1-2v)) and I can make similliar equations for C12 and C44. Also how did you calculate the anisotropic factor if I did not supply the C...

Homework Statement I am given c11, c12, and c44. What is poissons ratio ν and the E modulus E [100] for a single crystal for uniaxial strain in [100] (if Fe is isotropic)? ii) What is the anisotropy factor A? (iii) There is: sigma=[100 0 0; 0 100 0; 0 0 0]Mpa What is the transverse strain in...

Question: Explain the rules of reflection for different cubic lattices (SC, BCC, FCC) based on the Bragg ́s law. Help: If we have incident of X-rays, which planes have constructive/ distractive reflection? Why? Please calculate it for the following crystal planes. 001, 011, 111, 200, 210, 211...

As I understand the velocity gradient is the velocity that the layers of a fluid move in respect to each other. The divergence of the velocity is kind of the total rate of change of the field, since it is a sum of the components partial derivatives.

Thank you, so if the fluid is incompressible the layers do not have a velocity towards each other? If it was compressible the fluid layers would be able to compress towards each other?

Homework Statement An experimentalist has measured the u-velocity component of a two-dimensional flow field. It is approximated by u = (1/3)( xy) (y^2) It is also known that the v-velocity is zero along the line y=0. Homework Equations ∇V=du/dx+dv/dy (partial derivatives) The Attempt at a...

Homework Statement In this image : http://ezto.mheducation.com/13252703414204806874.tp4?REQUEST=SHOWmedia&media=2.83qs.jpg Why does the weight of the gate have a centroid at 2R/pi away from the force F? Homework Equations The centroid for a half circle in both x and y directions is =...

Flow exergy just means that exergy is flowing in or out. It might just be more relevant to substitute h for u+pv because that could be more relevant for an exergy flow analysis. Not sure, they are mathematically equivalent though, its just a matter of definition.

Thanks! Why would internal energy be equal for an ideal gas process??

Homework Statement Why does a gas behave as ideal if the Isotherm and Isenthalp are parallel. Homework Equations h=u+pv T1=T2, P1V1=P2V2 The Attempt at a Solution [/B] h1=u1+p1v1, h2=u2+p2v2 h2=h1 so u1+p1v1=u2+p2v2 and p1v1=p2v2 Does that mean internal energy for an ideal gas is zero? I...

Great! Thank you very much!