TER 201 E Thermodynamics
Homework I
Due date: 26.10.2011
1. A Bourdon Gage and a mercury (=13,600 kg/m3)
manometer are connected to a gas tank to measure its pressure.
If the reading on the pressure gage is 85 kPa, determine h in
mm.
2. A gas is contained in a vertical, frictionless piston cylinder device.
The piston has a mass of 10 kg with a cross-sectional area of 20 cm2
and is pulled with a force of 100N. If the atmospheric pressure is 100
kPa, determine the pressure inside. Also determine the boundary work
transfer, if the volume expands by 0.1 m3.
3. A 5 kg rock is thrown upward with a force of 150 N at a location
where the local gravitational acceleration is 9.79 m/s2. Determine the acceleration of the rock
in m/s2.
4. A horizontal 2 m diameter man-hole is located in the
bottom of a water tank as shown here. Determine the
extra upward force, F, that a man or machine must exert
on the man-hole cover to just barely lift it.
5. Express a 10oC temperature difference in Kelvin, Rankine and Fahrenheit.
6.
1
7.
8.
9.
10.
11.
12.
2
13.
14. Complete this table for H2O:
P, kPa
T, C
50
200
250
400
110
600
v, m3 / kg
4.16
Phase explanation
Doymuş buhar
Complete this table for H2O:
T, C
P, kPa
325
160
80
h, kJ / kg
x
0.4
Phase explanation
1682
950
500
800
0.0
3161.7
15. Complete this table for refrigerant-134a:
P, kPa
h, kJ / kg
T, C
240
81
4
-20
500
1400
362
20
x
0.27
1.0
16.
3
Phase explanation
17. An ideal gas is throttled to a lower pressure. During this process, (select the
correct statement)
(a) the temperature of the gas will increase.
(b) the temperature of the gas will decrease.
(c) the temperature of the gas will remain constant.
Why?
18. An ideal gas process for which P vk = constant, where k=cp/cv is an (select
the correct answer(s))
(a) incompressible process (b) isobaric process (c) adiabatic process
(d) isentropic process (e) isothermal process
19.
Verilen bir halde su buharının sıcaklığı 400C, özgül hacmi 0.02 m3/kg’dır. Su buharının bu
haldeki basıncını,
a. mükemmel gaz hal denklemini kullanarak,
b. genelleştirilmiş sıkıştırılabilme diyagramını kullanarak,
c. su buharı tablolarını kullanarak bulun.
20.
21.
4
22.
150
23.
5
24.
25.
6