BASIC
THERMODYNAMICS
RCT - 3
1. A 2.5 kJ of work is to be delivered 3. A rigid tank is connected by a valve
to a piston cylinder device with zero
on a rod from a pneumatic piston.
clearance. The tank contains 0.4m3
If the air pressure is limted to 500
of
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Chapter 4
The amount of energy needed to raise the temperature of a
unit mass of a substance by one degree is called the specific
heat at constant volume cv for a constant-volume process and
the specific heat at
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5.1
a)
xDP(t) = hS(t) 2hS(t-tw) + hS(t-2tw) h xDP (s) = (1 - 2e-tws + e-2tws) s Response of a first-order process, K h -t s -2t s Y (s) = (1 - 2e w + e w ) s + 1 s or Y(s) = (1 - 2e-tw s + e-2tw s) 1 + 2 s s + 1 Kh Kh 1 = = Kh 2 = s + 1 s =0 s
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4.1
a) b) c) d)
iii iii v v
4.2
a) b) c)
5 10 10 s (10 s + 1) From the Final Value Theorem, y(t) = 10 when t Y (s) = y(t) = 10(1-e-t/10) , then y(10) = 6.32 = 63.2% of the final value.
d) e)
5 (1 - e - s ) (10s + 1) s From the Final Value Theor
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6.1
a)
By using MATLAB, the poles and zeros are: Zeros: (-1 +1i) , (-1 -1i) Poles: -4.3446 (-1.0834 +0.5853i) (-1.0834 0.5853i) (+0.7557 +0.5830i) (+0.7557 -0.5830i) These results are shown in Fig E6.1
Figure S6.1. Poles and zeros of G(s) plott
2-1
Chapter 2
ENERGY, ENERGY TRANSFER, AND GENERAL
ENERGY ANALYSIS
Forms of Energy
2-1C In electric heaters, electrical energy is converted to sensible internal energy.
2-2C The forms of energy involved are electrical energy and sensible internal energy.
3-24
3-61 The properties of compressed liquid water at a specified state are to be determined using the
compressed liquid tables, and also by using the saturated liquid approximation, and the results are to be
compared.
Analysis Compressed liquid can be a
3-1
Chapter 3 PROPERTIES OF PURE SUBSTANCES
Pure Substances, Phase Change Processes, Property Diagrams 3-1C Yes. Because it has the same chemical composition throughout. 3-2C A liquid that is about to vaporize is saturated liquid; otherwise it is compress
1-34
Review Problems 1-85 A hydraulic lift is used to lift a weight. The diameter of the piston on which the weight to be placed is to be determined. Assumptions 1 The cylinders of the lift are vertical. 2 There are no leaks. 3 Atmospheric pressure act on