4.27 The rolling resistance of a car depends on its weight as: F = 0.006 mg. How long will a car of 1400 kg drive for a work input of 25 kJ? Solution: Work is force times distance so assuming a consta
Summer 2013
AME 310: Problem Set Ch8.4
Problem 8.67. Answer: T2=137.5 deg C, Sgen=0.1794 kJ/K
Problem 8.69. Answer: q=334.63 kJ/kg, s2-s1=1.0091/kJ/kg-K
Problem 8.87. Answer: Sair 0.661kJ / K
! As before, there are 2 particularly important classes of
problems to which this form of the 2nd Law is often applied
Steady-state, steady-flow
- the state of the control volume is constant wrt time
1
Entropy
20
Remember this illustration? Two cycles use different processes to go
from state 1 to state 2, but use the same process to return from state
2 to state 1.
Property 2
State 2
A
12
C
21
B
12
st
1
The
Law of
Thermodynamics
for a control mass (part1)
The origin of this law comes from experiments of Joule which
established the equivalence of work and heat.
Performing work on an adiabatically
VOTING RIGHTS AND WRONGS: Limiting the Black Vote from 1866-2013;
th
th
Here compare the efforts to prevent, discourage, or limit black voters in the 19 ; 20 and 21
centuries and the distinct social m
AMST- 252 Black Social Movements in the U.S.
Fall 2016
Professor Francille Wilson
TA: Athia Choudhury ([email protected])
Discussion Section: Tuesdays 10-10:50am VKC 154; 12-12:50pm TTH 106
Office Hour
AME 310: Engineering Thermodynamics
1. An open feedwater heater with two inlets and one outlet has the following conditions:
Steam enters inlet 1 at 0.8 MPa, 250C with a mass flow rate of 35 kg/s. Liq
1. Air at 35C, 105 kPa, flows in a 100 mm 150 mm rectangular duct in a heating
3
system. The volumetric flow rate is 0.015 m /s. What is the velocity of the air flowing in
the duct and what is the mas
1. Two cylinders are filled with liquid water, = 1000 kg/m3, and connected by a line with a closed
valve. A tank has 100 kg and B has 500 kg of water, their cross-s
AME 310 QUIZ 2 SOLUTIONS
Question1
Mass= 3 kg
Quality=x=0.3
P1=12056 kPa (Can be approximated to 12000 kPa to read from tables)
V2=2V1
T1=T2
Solution:
At P1=12000 kPa, from table B.1.2
vf=0.001527 , v
1. A piston/cylinder assembly contains air at 200 kPa and 350C. The 10 kg piston has a
diameter of 0.1 m and initially pushes against the stops. The cylinder now cools as heat is
transferred to the am
AME 310 QUIZ 1 SOLUTIONS
Question 1
Note: The given pressure (80kpa) is gauge pressure and not absolute pressure
Balance equation:
Po P ( gh) Po
10000 + 80000 = (density*9.81*h) + 10000
For water:
hw=
final state?
10a during this
HOMEWORK PROBLEMS
119
1. 10 kg of water in a piston cylinder arrangement exists as saturated liquid/vapor at 100
4.72 Ten kilograms of water in a piston/cylinder arrangek
Example 6.11
Assumptions:
1) The control volume is fixed in
space.
Until time t=t1, when the valve is
opened, we have steady state process
2) The state of mass may vary with
of steam flowing through a
Summer 2013
AME 310: Problem Set Ch9.3
Problem 9.55. Answer: W 0.247 kW .
Problem 9.73. Answer: W 365.8 kW .
Problem 9.90. Answer: w=0, q=187.1 kJ/kg, sgen=0.1626 kJ/kg-K.
Thermodynamics
In lecturing on any subject, it seems to be the natural course to begin with
a clear explanation of the nature, purpose, and scope of the subject. But in
answer to the question What is
Summer 2013
AME 310: Problem Set #2
1. Problem 2.30
2. Problem 2.34
3. Problem 2.38
4. Problem 2.40
5. Problem 2.46
6. Problem 2.56
7. Problem 2.64
8. Problem 2.69
9. Problem 2.74
10. Problem 2.75
1
Processes and Units
Process and Path
Process: any change
that a system undergoes
from one equilibrium
state to another one.
Path: The series of
states through which the
system passes during a
proces
Summer 2013
AME 310: Problem Set #3
1. Problem 3.35. Answer
P [kP A] T = [0 C ]
a
500
b
500
1400
200
8581
d
x
0.001002 undened
0.20
0.532
0.14302 undened
0.01762
0.8
151.86
c
v [m3 /kg
20
300
2. Probl
Use of Tables
Line of constant P (isobar) in T-V plane
T
D
B: Saturated liquid
Superheated vapor
C: Saturated vapor
Compressed liquid
A
V
The liquid-vapor coexistence line shrinks to the critical poin
Ideal Gas State Equations
Equations of state
Youve all seen one equation of state.
The Ideal Gas Equation of State
- Often called the Ideal Gas Law
- Relates P-v-T
Ideal Gas Law Assumptions:
- hard
Ideal Gas State Equations
Equations of state
Youve all seen one equation of state.
The Ideal Gas Equation of State
- Often called the Ideal Gas Law
- Relates P-v-T
Ideal Gas Law Assumptions:
- hard