Recent content by Krazer101

Anyone know where to start?

Homework Statement Consider a phospholipid bilayer membrane consisting of a mixture of 90% uncharged lipid and 10% singly charged acid lipid. Assume 68 Angstroms surface area per lipid head groups, and assume further that the charged lipids are uniformly distributed and immobile. The membrane...

Oh I see, thank you

Is it possible to raise the expansion to 3N instead of N to illustrate the other possible directions?

Homework Statement I am having trouble finding an expression for W (multiplicity) for a chain that can move in all possible directions (3 dimensions) Homework Equations Multiplicity is the number of possible states over total states. The Attempt at a Solution\ I understand for a...

Thank you, my main problem was understanding what would happen if the molecule did not completely occupy the cube or so. Thanks for explaining it to me.

So if we take the molecule in the center, then would the separation be the distance between the center of two cubes? The separation is the cube length? I am having trouble understanding how you determine cube length. Are we supposing the molecule takes up all the possible room in the cube?

anyone know where to start? I was thinking to use the density of the red blood cell but I am still having trouble figuring out how to eventually get to mean spacing

Homework Statement Calculate the mean spacing between hemoglobin molecules inside a red blood cell? Homework Equations Diameter of red blood cell = 5 microns 3*10^8 hemoglobin molecules in each red blood cell Volume of hemoglobin molecule = 8.71*10^-26 m The Attempt at a Solution...

Homework Statement Minimal growth medium for bacteria such as E. coli includes various salts with characteristic concentrations of mM and carbon source. This carbon source is typically glucose and it is used at 0.2% ( a concentration of 0.2g/100mL). a) Make an estimate of the number of...

I was thinking along the lines of that too, but I was just wondering if there was a better solution. The book solved many of the estimation problems by fitting the molecule, atom, etc into a 3-D shape, so I was thinking along those lines. Thank you for the help though, its much appreciated.

Homework Statement Estimate the volumes of the various amino acids in units of nm^3 Homework Equations V = 4/3*pi*r^3 The Attempt at a Solution Is it alright to treat the amino acids as spheres? Using this I was thinking of measuring the distance, atomic radii and bond length...

Is it possible to use method of sections on a frame or only on trusses? I have a frame that opposes a horizontal load and to find the forces in each member, I used method of sections. Is this right or is the only way to solve the forces is by analysis of each member.

When I'm calculating the bending moment in each member is it just the force times half the length?

I also have another question. When drawing the free body diagram, is it fine if I assume the external load is applied at a joint then some place on a member?