1.
3
A cubic box of volume 0.500 m is filled with monatomic ideal gas at atmospheric pressure and at 20.0!!e. The box is closed and heated to 180!!e. How much heat eriergy is needed to What is the change of internal energy when the temperature is raised from 20.0!!C to 180!!C? 4
2.7 X 10 J.
b) 3.8 X 104 J.
4
c) 1.7 X 10 J.
4.1XI04J.
e) 5.3 X 104 J
a)
L/
I~ = ~O t A,?V
A
A
-
3
:2)'\. 'R
~, VI
3
.AT = '2 T. ,AT
@
2.
The Neon atom is 5 times more massive than the Helium atom. A tank contains 1.00 kg of Helium s and 1.00 kg of Neon gas at 200!!e. The average kinetic energy per Helium gas atom is a) the same as that of the Neon gas. I:)
5 times more than that of the Neon gas.
Z. ~ if 1. =.
~T c) '1/5 times more than that of the Neon gas. d)
INS of that of the Neon gas. e)
liS of that of the Neon gas. ~
3.
,-.2"2
How many atoms are there in a 3.4-gram copper penny? (mcu=63.ssu) 19 a) 3.2xl0
2o b) 3.2x10
c) 3.2x1021 22
@3.2 x l0
23
e) 3.2xl0
3:1- 'J­
4.
A chunk of 0.5 kg ice at/l0!!C is placed in 2.0 kg of "iced" tea at 20!!e. What is the final temperature of the mixture? a)
:l
~~~;;~.
d)
7.0!!e.
0.0!!e.
@
s.
S.O!!e.
0lj *2'00
* tlO) -t
3
6.; k
I
">
333 xlO
2 X4H?b
(
\
X 2.0)
A heat pump operates between the low and high temperatures, T_L=-lO.O!!C and T_H=20.0!!e. What
is the "ideal" coefficient of performance (COP)?
®
b)
c)
d)
e)
6.
9.8
8.8
7.8
0.67 6.8 =
21-3
+ 1.0
80
Heat energy is used to convert 0.65 L of 100·C water (denSity 1.00 kg/L) to 100·C steam at a volume
of 1086 L. What is the change of the internal energy of water?
fa}) 1.4 X 106 J
'0) 1.1 X 105 J
.6
W
6
c) -1.4 X 10 J 5
d) -1.1 X 10 J e) OJ U = G> -
7.
The pendulum in a grandfather clock is made of brass and keeps perfect time at 172C. How much
time is gained or lost in a year if the clock is kept at 25 2 C? (Assume the frequency dependence on
length for a simple pendulum applies.)
@ 40 min
b) 65 min
c) 25 min d) 80min
e) 15 min
i
~ ==
t: (
t2..- t I
A
-=
_1.
LI
-
-
[f+ ()( AT
r
( \
t
JH fiAT -I)
I
€
.::: ~ I + I q )( 10
40}~
-
X-
(z5' -c-:r-)
;L...
d.. t· 8. To make a secure fit, rivets that are larger than the rivet hole are often used and the rivet is cooled
(usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm indiameter is to be placed in
a hole 1.869 cm in diameter at 20°C. To what temperature must the rivet be cooled if it is to fit in
the hole?
a) -49°C
b) -59°C
c) -89°C
-69°C
-79°C
can
'ef 9. An ordinary glass is filled to the brim with 350.0 mL of water at 100.0°C. If the temperature
decreased t020.0°C, how much water could be added to the glass?
a) 3.35 mL
b) 1.65 mL
c) 2.32 mL
d) 6.24 mL
~5.12mL
10. An aluminum bar has the desired length when at 15°C. How much stress is required to keep it atthis
length if the temperature increases to 35°C1
s
2
a) 3.5x10 N/m
7
(1))) 3.5xl0 N/m2
'c( 3.5x106 N/m2
d) 3.5x104 N/m2
8
e) 3.5x10 N/m 2
11. Calculate the density of oxygen at STP using the ideal gas law.
0.34kg/m3
) 1.43 kg/m 3 c 3.12 kg/m 3
d) 2.33 kg/m 3
e) 4.12 kg/m 3 ~
.f.
f = -
'tJl0
2­
RT 12. ~imate the rms speed of an amino acid whose molecular mass is 89 u in a living cell at 37°C.
a) 290 m/s
) 900 m/s
c)Om/s
d) 50 m/s
e) 70 m/s
1fY'hc-5
_
-
f¥
f'-'
3-kT.
-;-
_---~-__­
_Zo ;r
:3xl·ggxlo
-
k·g~O.
-iT
8' q>( H6 X (0 .k}
13.
A helium-filled balloon escapes a child's hand at sea level and 20;0°C. When it reaches an altitude of 3000 m, where the temperature is 5.0°C and the pressure is only 0.70 atm, how will its volume compare to that at sea level? (Assume the helium is an ideal gas. ) a) 0.9 times the original volume (bf)1.4 times the original volume
'c(' 2.5 times the original volume
Z ; l1-RT2.
d) 7.1 times the original volume e) 4.3 times the original volume PI", :; 1't'RT.
rl-V
14.
A cubic box of volume 5.1 X 10-2 m 3 is filled with air at atmospheric pressure at 20°e. The box is closed and heated to 180°C. What is the net force on each side of the box?
l..
a) 7.6xl0sN
ft
TL Ib
.-1 3 do
b) 7.6xl06 N
r2 - T~ r,
- c..:\ •
V· _
c) 7.6xl02 N
d) 7.6xl04 N
3
@)7.6 x l0 N
15.
F
m..:t-
2­
. A =- ..I= - t) P . d :::
Tr' .
2.'
~
N 1_'
1 molecules/breath
85 molecules/breath
e)
=.
~. e 0
c)· 19 molecules/breath
150 molecules/breath
_
1\1.. -
79 molecules/breath
.. I
/2 (;) XfO"-3
\..~
•
J) . L ~T
tJ del; Ie. 0
-Q-z.- ­
4'7rR' "'~
1'4l;:tye,,-~
.:::::
......2. 0
-3';)" ''It...
XIO
What would be the rms speed of a protem of molecular mass 50,000 u at 37°C?
a) 1.5m/s
b) 0.15 m/s
34 m/s
d) 12 m/s
e 0.015 m/s
<W
17.
~
(r -f )
'lJ
_
~
~
tms ­
h\­
Air that is at its dew point of 5°C is drawn into a building where it is heated to 25°C. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air. a) 7.5% (b)) 27.5%
':Rtf:.
L
160% :;.
'c(
g=r ~ '*
17.5%
z=r. C; %
3.1'r- )( 1I>
d) 37.5% e) 47.5% 18.
z./3 _ V
Estimate how many molecules of air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.] a)
16.
=
A=
What is the approximate pressure inside a pressure cooker if the water is boiling at a temperature of 120"C? Assume no air escaped during the heating process, which started at 20°C. Gi) 1.97 atm
b) 2.37 atm
c) 1.57 atm d) 1.27 atm e) 3.27 atm I.q
5"
q)( 10 1'll... == I. q=t
td-It\
19.
The lowest pressure attainable using the best available vacuum techniques is about 10-12 N/m
2
•
At
3
such a pressure, how many molecules are there per em at O·C? 30 molecules/cm 3 I\J
.h
IV
3
-'"
b) 300 molecules/cm
'r
V<
3
V
c) 3000 molecules/cm
3
d) 3 molecules/cm
e) 30000 molecules/cm 3 @
.1.-,-
V::
­
f
~r
20. A space vehicle returning from the Moon enters Earth's atmosphere at a speed of about
40,000 km/h. Molecules (assume nitrogen) striking the nose of the vehicle with this speed
correspond to what temperature? (Because of this high temperature, the nose of a space vehicle
must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze
upon reentry.)
1~
a) 1.4xl02 K
...LI')\ 'If = ' - ~T
3
b) 1.4xl0 K
:l.
2. 4
c) 1.4xl06 K
~ _,
d) 1.4xl0 K
~
twtr @1.4xl0S K
3~ T
21. In humid climates, people constantly dehumidify their cellars to prevent rot and mildew. If the cellar
in a house (kept at 20·e) has 95 m 2 of floor space and a ceiling height of 2.8 m, what is the mass of
water that must be removed from it to drop the humidity from 95% 1j a more reasonable 30%?
~~:~~: ~ 8.0 kg
d) 20 kg
e) 0.5 kg
tq~/o ~
P"'j
fJi>/u
-'It.:::
o.-q5" .(2. 33 }(f~ ~)
0,30 (2.'33 XIO Po.. )
:=
/;
(. ~q~b -
P30:t.
)
V
_ .
N ~ ')t. • "'H20 - Z.q g- -k3­
22. During exercise, a person may give off 180 kcal ~iteat in 30 min by evaporation of water from the
skin. How much water has been lost? (The heat of vaporization at room temperature is about 2450
kJ/kg, or 585 kcal/kg.)
a) 780 mL
0.310
b) 63 mL 180 -icoJ
r
c) 150 mL
~ ~f) ~ cd2/-k. d) 280 mL @310mL
23. The solar constant is 1350 W /m 2 • Estimate the rate at which the Earth receives energy from the Sun.
(af) 1.73xl017 W
2­
'b( 2.25xl017 W
17
c) 3.75xl0 W
'f d) 4.12xl0 17 W e) 0.78xl017 W I
"t'rR
A
.sola.
­
24. Assume the Earth radiates an equa'i amount back into space (that is, the Earth is in equilibrium).
Then, assuming the Earth is a perfect emitter (e = 1.0~ estimate its average surface temperature.
a)
b)
c)
d)
-6 Q C lQC
10QC
-14QC
@5 C Q
/31)0
<T
.:!L . T'R
~ 2­
4
2..
=
e.
(J"
L.
4
(4111< ). T (3 r; 0 =
e . -4 <a­
25. During light activity, a 70-kg person may generate 200 kcal/h. Assuming that 20% of this goes into
useful work and the other 80% is converted to heat, calculate the temperature rise of the body after
1.00 h if none of this heat were transferred to the environment. a) 0.72C hl c .6
XI03
b) 3.22C
c) 12.2C
T
®
=
AT:::
2.8 2 C
e) 5.5 2 C
x:t.l~&
loa
* go% 2..=t6 0c..
26. Estimate the rate atwhich heat can be conducted from the interior of the body to the surface.
Assume that the thickness of tissue is 4.0 cm, that the skin is at 34°C and the interior at 37°C, and
that the surface area is L5 m 2 • Compare this to the measured value of about 230 W that must be
dissipated by a person working lightly. This clearly shows the necessity of convective cooling by the
blood.
3 0C
A<Q
a)
200 W
2W
c) 20W
0.2W
e) 0.02 W
il.-t
_.-k
A. .5..
0,
.6X
cW
2.~ I,l) ... .1.
22.':;;
-
­
0,04
/!loS'l(
h\
W
27. An ideal gas expands isothermally, performing 3.40x 10 3 J of work in the process. The heat
absorbed during this expansion.
AU=D
L\U+ W
3
j!~ - 3.40 X 10 J ~3.40XI03 J 0J d) 1.70 X 10 3 J e) -1.70xlo3 J c)
28. 1.5 moles of an ideal monatomic gas expand adiabatically, performing 7500 J of work in the process.
at is the change in temperature of the gas during this expansion?
~
a)
-400K
<S2
-500K
c) +200K
~
d) +100K e) Not enough information to determine =0
tr == -
=.t1
VJ =
W
- 1-t)DOJ":-
U+
~
2
n...R. AT
29. What is the change in entropy of 250 g of steam at 100°C when it is condensed to water at 100°C?
3
a) -2.5xl0 J/K
l
)
/'
3
+2.5xl03 J/K
-'f>,~50 . 22bO XIO
3
c -1.5xl0 J/K
L1 S =.
3
K
3
+1.5xl0 J/K e) 0 J/K ~
r _
1-.3
30. 1 kilogram of water is heated from O°C to 100°e. Estimate the change in entropy of the water.
3
a) 8.4xl0 J/K
.313
3
~ -8.4xl0 J/K
3
(S) 1.3xl0 J/K
d) -1.3xl03J/K
e) 0 J/K ..65
=
f
31.
A person decides to lose weight by sleeping one hour less per day, using the time for light activity.
How much weight (or mass) can this person expect to lose in 1 year? (Assuming no change in food
intake and that 1 kg of fat stores about 40,000 kJ of energy).
®~~~b
(230 - 'fo)
c) 23 Ib
d) 30lb X
3bOO s x36.5 xz4
4
. 3 ~l/'
OpOC l< 10 '/-k}
=',
2.b
k~ e) 181b
32. A nuclear power plant operates at 75% of its maximum theoretical (Carnot) efficiency between
temperatures of 625°C and 350°C. If the plant produces electric energy at the rate of 1.3 GW, how
~
"1':3 )
1.1
\AI
much exhaust heat is discharged per hour?
a) 9.6xl011 J/h (0::"0-+2.. 1'=
2- _
2f 3
b) 1.6xl014 J/h
C?"fr)
~H
'w-t6ZL.
13
c) 9.6xl0 J/h (Ci)) 1.6xl013 J/h
12
9.6xl0 J/h *" { - 62,t
'ef
33. What volume of water at O"C can a freezer make into ice cubes in 1.0 hour, if the coefficient of
performance of the cooling unit is 7.0 and the power input is 1.0 kilowatt?
fa)) 76 L
~ 3.3 )1.10
'-6) 27L
Cop
~ =:(. 0 -11
(3
=
c) 45 L
G(
d) 15L
e) 84 L
vJ
=
:(,O
/.'~
'\
*~.o XID *3600) ==
3.r/)
/~q
(
L
Wl
= (\)11­
t-
m
34. A 10.0-kg box having an initial speed of 3.0rn/s slides along a rough table and comes to rest.
Estimate the total change in entropy of the universe. Assume all objects are at-room temperature
(293 K).
a) O. J/K
b) 0.31 J/K
c) -0.31 J/K
d) -0.15 J/K 0>0.15J/K T
35. A dehumidifier is essentially a "refrigerator with an open door." The humid air is pulled in by a fan
and guided to a cold coil, where the temperature is less than the dew point, and some ofthe air's
water condenses. After this water is extracted, the air is warmed back to its original temperature
and sent into the room. In a well-designed dehumidifier, the heat is exchanged between the
incoming and outgoing air. This way the heat that is removed by the refrigerator coil mostly comes
from the condensation of water vapor to liquid. Estimate how much water is removed in 1.0 h by an
ideal dehumidifier, if the temperature of the room is 25"C, the water condenses at 8"C, and the
dehumidifier does wor.k at the rate of 600 W of electrical power.
a) 0.41 kg
QI_
~ 0.62 kg
"=.
----­
@) 14.6 kg W
T....-Tlif­
T;:
COp
d) 4.8 kg e) 24.3 kg .
<5.;>1- :;:.
z.B (~
~
'* ~o vJ
~ 3600s
L + = ~4;-o -k~;:-CL
e\i~"YM.fot"
I' (J
*
11\
= 14-. S:f.
1c.3­
)
-
m
L
<t
36.
1.0 kg of water at 30°C is mixed with 1.0 kg of water at 60°C in a well-insulated container. Estimate
e net change in entropy of the system.
a 9.3J/K
T
.
A90J/K
.6 S = m C jl Tf.
Me j.N.. _ f
..I­
• K
c 0 J/K I
T.
2...
Tz
d) ~9.3 J/K e) -490J/K j
+
C[!
37. An ideal monatomic gas is placed in a tall cylindrical jar of cross-sectional area O.080m2. A
frictionless 0.10-kg movable piston is placed vertically into the jar such that the piston's weight is
supported by the gas pressure in the jar. WheA the gas is heated (at constant pressure) from 25°C to
55°C, the piston rises 1.0 em. How much heat was required for this process? Assume atmospheric
pressure outside.
~100J
A
~200J c) 300 J
d) 400J
e) Not enough information to determine
p
o
v
38. When a gas is taken from a to c along the curved path in the above Figure, the work done by the gas
is W = -35 J and the heat added to the gas is Q =-63 J. Along path abc, the work done is W = -48 J.
What is Q for path abc?
a) +56J
b) +76J
c) -56J
@-76J
e) +26J
39. If ~ =tl}" what is Wfor path cda
@
b)
c)
d)
e)
24J
-24J
48 J
-48 J
+32 J
.
40. What is
a) 35 J
afor path cda?
b) ·35 J
c) 76J
(d))52J 'e) -52J Use blue book to do following problems, show your work
41. Find the value of the line integral
JdF, where dF=xldx+~ydy
a) Along a straight line from (x,y)=(1,I) to (1,3); then (1,3) to (4,3); then (4,3) to (1,1).
b) Along a straight line from (x,y)=(I,I) to (4,3)
J
42. Find the value of the line integral dF, where dF=xydx+~dy
a) Along a straight line from (x,y)=(1,I) to (1,3); then (1,3) to (4,3); then (4,3) to (1,1).
b) Along a straight line from (x,y)=(I,I) to (4,3).
43. Find the value of the line integral JdF, where dF=(2x/-4x)dx+2~ydy
a) Along a straight line from (x,y)=(1,I) to (1,3); then (1,3) to (4,3); then (4,3) to (1,1).
b) Along a straight line from (x,y)=(l,l) to (4,3).
44. An equation of state is given by F(x,y,z)=(x-a/x2)(y-b)-cz=0.
a) Find (dx/dy)z; (dy/dz)x; (dz/dx)y
b) Find (dx/dY)zx(dy/dz)xx(dz/dx)y
Parameters
2
k=1.38xl0. 23 J/K, NA=6.022xl023 , R=8.315 J/K, 1 atm=1.013xl0s N/m
Heat capacity of ice is 2100 J/kg!:'!C, of water is 4186 J/kg!:'!C.
Latent heat of evaporation of water at 20!:'!C is about 2450 k.l/kg, at 100 !:'!C is about 2260 kJ/kg
Latent heat of fusion for water at 0 !:'!C is 333 kJ/kg
Linear heat expansion coefficient of brass is 19x10.6 /!:'!C
Linear heat expansion coefficient of iron or steel is 12xl0.6 / 2C
6
6
Volume expansion for the ordinary glass is 27xl0. /2C, and for water is 210xl0. /2C.
mcu=63.55 u
Young's modulus for Aluminum is 70xl09 N/m2