Recent content by dweeegs

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    Concentric Tube Heat Exchanger - Clarification on Energy Balance

    Feel dumb now, I was up awake for an extremely long stretch of time and read the equation wrong... in my mind somehow the variable subscripts were flipped. I am not confused after a good night's rest :D
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    Concentric Tube Heat Exchanger - Clarification on Energy Balance

    I'm trying to model a Transfer function for the response of the deviation in temperature of water coming out of the concentric tube heat exchanger in response to an input velocity of water function. THE PROBLEM I start the derivation with a couple equations in Seborg's Process Dynamics...
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    Uncertainty Product for a hydrogen-like atom,

    Homework Statement Calculate the uncertainty product ΔrΔp for the 1s electron of a hydrogen-like atom with atomic number Z. (Hint: Use <p> = 0 by symmetry and deduce <p^2> from the average kinetic energy) Homework Equations All I have is the wavefunction. For a 1s, it takes the form...
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    Quantum Mechanical Operators - A Question Or Two

    A couple questions: is mass quantized? Energy is quantized, and momentum has eigenvalues for its operator so I took that to mean that momentum is also quantized. If those two are true (might not be! I'm new to this :-p), following E^2 = (pc)^2 + (mc^2)^2 Would that not mean that mass is...
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    Classical Probability with a falling ball problem

    http://i793.photobucket.com/albums/yy215/dweeegs/probability_zps12a67dfb.png The picture shows everything needed. This is a worksheet on the similarity of classical probability to the probability of finding a particle in a box (Schrodinger stuff etc) Basically there's a ball falling...
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    Mass Transfer - Boundary Conditions

    Homework Statement An airborne spherical cellular organism, 0.015 cm in diameter, utilizes 4.5 gmol O2/(hour kg of cell mass). Assume Sh = 4 for external convective resistance to O2 transfer to the cell. (Sh = kd/D is based on diffusivity in the gas phase). Assume zero-order kinetics for...
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    Mass Transfer - Need help on setting it up

    So let me if I understand you correctly, The reaction isn't occurring while the gas is diffusing, thus Ra isn't included in the differential equation. However it is introduced when we consider our boundery condition? Something along the lines of: -D(dCa/dr) = kCa at r=R2 Is that...
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    Mass Transfer - Need help on setting it up

    Homework Statement Not looking for solutions, just confused with the problem set up. Need help with the boundary conditions. Here it is: A porous ceramic sphere of radius R1 is kept saturated with a pure component liquid A. The vapor pressure of A is 50 torr. This sphere is surrounded by a...
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    Fluid dynamics of entry region in a pipe

    I'm going to change my assumption for velocity in the x-direction. The fluid would be coming from both the top and bottom of the pipe and meet in the middle, where vx=0. Obviously this means there's a change in the x-direction with the x-component of the velocity. so now vx is a function of x...
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    Fluid dynamics of entry region in a pipe

    Homework Statement Steady, laminar flow of an incompressible Newtonian fluid with constant physical properties. The area of interest in the problem is in the entrance region between two wise, horizontal parallel plates separated by distance 2B. z is in the direction of flow and x is the...
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    Thermodynamics Question (Maxwell Equal Area Construct)

    Homework Statement The problem is a long one. Basically we have to use Maxwell's Equal Area Construction. "With Mathcad, find Psat and the corresponding saturation volumes at T=400K for n-hexane based on the van der Waals' equation of state. Furthermore, turn Psat into a function of...
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