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
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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
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
a) b) c) d)
iii iii v v
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.
5 (1 - e - s ) (10s + 1) s From the Final Value Theor
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
ENERGY, ENERGY TRANSFER, AND GENERAL
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.
3-61 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
Analysis Compressed liquid can be a
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
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