This preview shows pages 1–8. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERING
UNIVERSITY OF CALIFORNIA, BERKELEY
E1 1, MARCH 2, 2005 MIDTERM EXAM 1 Name and Student ID: SQLVTE 0“] Instructions: Answer the questions that follow directly on these pages in the spaces
provided. Use the back of the page if you need more room for your answer. If you
believe there is insufﬁcient information provided to answer a question completely, state
reasonable additional assumptions and proceed from there. This exam is closedbook/closednotes. Calculators are not allowed. Time: 50 minutes. Question: Score: Out of:
l _ 5
2 __ 5
3 __ 4
4 __ 5
BONUS __
TOTAL 1 9 Useful Data and Formulas: Ideal gas law: PV = nRT
Hydrostatic equation: dP/dz = pg CMFR general equation: dC/dt = S — LC
Solution to CMFR general equation: C(t) = Coexp(Lt) + (S/L)[1exp(Lt)]
Exponential growth equation: dN/dt = rN Logistic growth equation: (:l—Ij = rN[l — 1. AIR AND WATER BASICS (1 point each) a) The value of the ideal gas constant depends on its units. Write one valid set of units
for the ideal gas constant (just the units, not the value). Rt Ly] Poww‘} of of T
E“ wm\ K In” “HULK V“th W‘Q\ ' b) What are the names of the two layers of the atmosphere nearest the ground, and what
is fundamentally different within these layers that distinguish them from each other? ﬁll; Opes 7 +Kw‘3zxoﬁ "\NZ. AKQFK’QSKS “\N/ ﬁlth“ d1? c) Sketch a plot of atmospheric pressure as a function of altitude and identify the point of
maximum pressure. State how pressure varies with altitude. P AxCrKaxS scape? m‘riulLt wﬂm
mam/3 hash Pzﬁwx P) PVK‘SSvVK Java 1. AIR AND WATER BASICS — continued d) Given the follow components of the hydrologic cycle, calculate the characteristic
lifetime of a water molecule in the ocean. Depth of ocean = 103 m IT] 1, S‘YOQ\< / ﬂ
Volume of ocean = 1018 m3 bw
Precipitation onto ocean = 4 x 1014 m3 yr“ Runoff into ocean = 1014 m3 yr"l Evaporation from ocean = 5 x 1014 m3 yr'l glow : 2v aeomi‘w ’4 (pYZ<;‘3;3rQ3V:0n ~l W“ 0££> rx, Q‘X'm‘ﬁ /,
v ‘ — Smo‘lm'i/W «'33: ﬂog qt 3 loooxiv e) Assume that the density of water is constant. Sketch a plot of pressure as a function of depth in the ocean and identify the point of minimum pressure. State how pressure varies
with depth. P, PYKSS UYK
\ J (km
A? = {c3131
P" mm =— 33 (1%)
l): mm + 9 PK '86va {Mora sagas l ivx’inlel wM\ New: A3019  2. POPULATION GROWTH (1 point each) a) Sketch a logistic growth curve and label the axes. Deﬁne K and identify it on the
curve. +2 ivv‘K b) What is the population size when dN/dt attains its maximum value? K/l c) Given the governing equation for logistic grth on the front page of the exam, derive
an expression for the instantaneous growth rate, R. R I JN/QH: “I
N K POPULATION GROWTH — continued d) What are the ﬁrst three phases of demographic transition?
1 leiwlx MA We} (ixqilx rrﬁZS :3 Slow popvia‘l‘lm Brawl
l— Dszmlx m3va clzavsmsa sip atom—TL wk M2613“ (meta tweaks
"gt Se;er (casts AK<VZQ$K “$19 OSMWWL Sim/«S 6) Assuming an annual exponential growth rate of 35%, about how many years will it
take for a population to increase from 100 to 400? '\ EON \00 +0 “‘00 \S We \\,\ g t\/\ 01 HQ‘WOW Squ.
5 P r
\09 t \ .
100% bwlolilwb a":th 3T3 1):, 33.
tree v04) S 2““ gt“ O’R 3. HOT SOUP (4 points) I prepared a bowl of tomato soup (mass = mg). It was too hot to eat, and it was in a well
insulated bowl, so I knew it wasn’t going to cool anytime soon. I decided to put an ice
cube (mass = m) into it to cool it. As I was stirring the ice cube into the soup and
watching it melt, I wondered how much the soup would cool. If the initial temperature of the ice is Ti = 0 °C, and the initial temperature of the soup is
Ts, derive an expression for the ﬁnal temperature of the soup, Tf. Assume that the speciﬁc heat of the soup, c, is equal to that of water, and assume that the
speciﬁc heat of water is constant in the range from 0 to 100 °C. Deﬁne all symbols in your equations unless they are explicitly deﬁned above. Fmsxl ionimhoz. i’ lurkl: \o‘ﬂ \m/ SQVF 5 i‘ﬁvﬁ Buibzui la. wqutg ; W\}>\ + rmc ET;
I i 3mg \mcmv Mil \M QM \wwﬁ “RV MS V ‘ i i . 3v, Q ‘ i , ® ‘0‘ “MRS I Whig wu’ww wooimi ‘Io fwa *3:va ’
k f QW’M @cws ADV lama) . : \Q‘vmmeg oi ism (“my ‘, ATS : (\AQM‘3X ix» T 0K 5m? :: “TS :. (\AQWB‘E \‘k l4? 3 "Ti 2 \I —' CC = L?
VaRw \lV W\—‘r3 3v\0‘3‘V\\/‘V\\43) jiégi “ T3 "‘ WNSQ—(g .a» V‘\\7\ ‘i WM mi HOLY SMOKES — MATERIALS BALANCE (5 points) It is raining outside and your friend insists that you have a barbeque inside your single
room apartment shaped like a box. Barbequing indoors is very dangerous, as you are
well aware. To prove it to your ﬁiend, you calculate the concentration (C, g m'3) of
carbon monoxide gas (CO) in your apartment that would result from such a stunt. You make reasonable assumptions for the barbecue CO emission factor (E, g s") and your
apartment ventilation rate (Q, m3 3'1) and volume (V, m3). a) Write the appropriate materials balance equation for this system. Do not assume
steady state, but state all other assumptions that you make. o\<;<vvwv\o9ri 01/“ 2: \‘hg\b‘v~1 «k QW\\‘$3lO\”s  D‘JW£\O‘W ~— QKKG‘Y RSSVWZ i\I\~ii\ow : (£23k qivi§ an; clam7 : (is (comm 0%in
fell mm Liz HOLY SMOKES — MATERIALS BALANCE — continued (I) You decide to have the barbeque in your apartment while you wait outside in the rain.
The barbecue lasts several times longer than the characteristic time of the system. To
determine when it is safe to go back inside, you calculate the CO concentration as a
function of time, C(t), after the barbeque is extinguished. Derive an expression for C(t)
that is valid afﬂ the barbeque is extinguished. Deﬁne any new parameters (i.e.,
symbols) that you introduce. I. C H) I CB QM) (*.§~é;>
whzva t i3 +i‘mz Stuck w as 2min sigh“; mm £2 0)
5m; CO R “th CDW‘ﬁvbﬁtiom $373,2{MMKQ FUN—IV CV a, BONUS QUESTIONS (0.5 point each) In the movie “The Next Industrial Revolution,” what did waste equal? Weak 5 be The Kyoto Protocol was ﬁnally positioned to enter into force when it was ratiﬁed by
which country? Russia ...
View
Full
Document
 Spring '09
 CHOW

Click to edit the document details