Name: _
BioE 104 Homework 1
Please attach this problem statement to your completed homework
1. (_ out of 4 points) Our random walk analysis in class indicated
that, for a number of particles all starting at x = 0 at t = 0, the meansquare displacement <x2>

Name: _ BioE 104 Homework 1 Due Friday 1/28/11 at 11AM Please attach this problem statement to your completed homework 1. (_ out of 4 points) Our random walk analysis in class indicated that, for a number of particles all starting at x = 0 at t = 0, the m

Name: _
BioE 104 Homework 7
Please attach this problem statement to your completed homework
1. (_ out of 3 points) Transport Phenomena in Biological Systems
Problem 2.15.
2. (_ out of 5 points) Transport Phenomena in Biological Systems
Problem 2.10. List

!"#$%&'$()*%&#+'!',-'./0'!$(123'4/./' '
1. (_ of 15 points) Steady-state convection and diffusion through a flat membrane. A porous membrane has been designed as part of an industrial process. The membrane is 5 cm thick with an area of 100 cm2, and is des

BioE104 Homework 6 Solutions
1. The balance equation for the two systems is
.
(1A)
The total amount in the systems does not change or
,
,
.
(1B)
Using (1A) we may write
,
Defining
,
,
,
.
(1C)
/ , (1C) becomes
1
.
(1D)
Rearranging (1D) gives
.
1
(1E)
Inte

2.15. For fluid 1, since the resulting velocity is linearly related to the original velocity, the fluid
is Newtonian.
For fluid 2, there is no linear or power dependence between the velocities suggesting that the
fluid is a Bingham plastic. Applying Equat

Problem 1
!
Given:
Dij = 2.0*10-6 cm2/s
L = 3 mm = 0.3 cm
t = 12 hours = 43200 s
,
First, calculate = Dijt/L2 = (2.0*10-6 cm2/s) (43200s)/(0.3cm)2 = 0.96
Unfortunately this value is not shown

Name: _
BioE 104 Homework 10
Due at the beginning of class, 11:10AM, Friday 4/19/2013
Please attach this problem statement to your completed homework
1. (_ out of 2 points) Prairie dog
burrows are elaborate and have
entrances at different heights. A
protr

Name: _
BioE 104 Homework 11
Due at the beginning of class, 11:10AM, Friday 4/26/2013
Please attach this problem statement to your completed homework
1. (_ out of 6 points) A cylindrical membrane has an inner radius
R0, outer radius R1, diffusivity DM, an

Name: _
BioE 104 Homework 12
Due at the poster session, Monday 5/6/2013
Please attach this problem statement to your completed homework
1. To trace ocean currents, a sphere with an initial radius of 1.8 cm is
to be dropped into the ocean. The sphere is ma

Name: _
BioE 104 Homework 9
Due at the beginning of class, 11:10AM, Friday 4/12/2013
Please attach this problem statement to your completed homework
1. You are applying dimensional analysis to determine
the energy of an atomic explosion. After much
delibe

Problem ( oints)
Roadmap:
- model the trachea as a pipe
— deﬁne Reynolds number for a pipe
- find characteristic parameters (Lchanp air: P a?)
- find air velocity for normal breathing vs. sneezing
- compute Reynolds numbers for both cases
— decide whether

BioE104 Homework 2 Solutions
1. Using the Stockes-Einstein equation (purely theoretical) the diffusion coefficient is:
.
(1A)
For a spherical shape
6
so
.
6
(1B)
Substituting the values gives the result
1.38
6
10
8.90
25
10
.
273.15
0.347
2
1.41
10
/ .
1

BioE104 Homework 5 Solutions
[For question 3: See the files section of bcourses].
1. At time = 12 hours, =
456
)(&.,123
)
./
6
(%.% 78)
(%& '()(*+,
= 0.714
The total amount of solute in the system will be the volume of the membrane times the average
con

BioE104 Homework 4 Solutions
1. As seen before, the 1D diffusion equation in cylindrical coordinates without reaction is
,
(1A)
with the three boundary conditions
0,
0
(where is the initial concentration in
the membrane),
0,
0
where constant is the membr

BioE104 Homework 3 Solutions
1. The diffusion equation in cylindrical coordinates is
1
1
.
(1A)
There is no reaction
0, the problem is steady state /
0, axi-symmetric /
0 (no
diffusion in direction), and /
0, i.e., the cylinder axial length is very large.

BioE104 Homework 1 Solutions
[For the lab question (question 4): See the files section of bcourses, under Lab 1 directory, for
Lab01_2D.jpg and Lab01_3D.jpg]
1. In this problem we are given a continuous concentration distribution
, , so instead of a
summa

Diusion (draft version)
Terry D. Johnson
UC Berkeley Bioengineering
March 16, 2015
Chapter 1
Random Walk
Ficks first law is:
Nx
direction
=
Dij
@c
@x
amount
Ficks law says that the flux ( areatime
) of solute diusion in the x-direction
@c
is the product o

Contract for Final Project
We, the undersigned, have agreed to work together on a final research
project. Each of us understands that we are jointly responsible for the final
product as a whole, and though we may split the work up amongst
ourselves, all o

Name: _
BioE 104 Homework 7
Due at the beginning of class, 11:10AM, Friday 3/15/2013
Please attach this problem statement to your completed homework
1. (_ out of 3 points) Transport Phenomena in Biological Systems
Problem 2.15.
2. (_ out of 4 points) Tran