
Fundamentals of Thermal-Fluid Sciences
5th Edition
ISBN: 9780078027680
Author: Yunus A. Cengel Dr., Robert H. Turner, John M. Cimbala
Publisher: McGraw-Hill Education
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Question
Chapter 20, Problem 67P
To determine
The significance of effective thermal conductivity of an enclosure.
The ratio of effective thermal conductivity to thermal conductivity.
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find the laplace transform for the
flowing function
2(1-e)
Ans. F(s)=-
S
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0 a
2a 3a 4a
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14) f(t)=1, 0
Find the solution of the following Differential Equations
Using Laplace Transforms
1) 4y+2y=0.
y(0)=2.
y'(0)=0.
2) y+w²y=0,
(0)=A,
y'(0)=B.
3) +2y-8y 0.
y(0)=1.
y'(0)-8.
4)-2-3y=0,
y(0)=1.
y'(0)=7.
5) y-ky'=0,
y(0)=2,
y'(0)=k.
6) y+ky'-2k²y=0,
y(0)=2,
y'(0) = 2k.
7) '+4y=0,
y(0)=2.8
8) y+y=17 sin(21),
y(0)=-1.
9) y-y-6y=0,
y(0)=6,
y'(0)=13.
10) y=0.
y(0)=4,
y' (0)=0.
11) -4y+4y-0,
y(0)=2.1.
y'(0)=3.9
12) y+2y'+2y=0,
y(0)=1,
y'(0)=-3.
13) +7y+12y=21e".
y(0)=3.5.
y'(0)=-10.
14) "+9y=10e".
y(0)=0,
y'(0)=0.
15) +3y+2.25y=91' +64.
y(0)=1.
y'(0) = 31.5
16)
-6y+5y-29 cos(2t).
y(0)=3.2,
y'(0)=6.2
17) y+2y+2y=0,
y(0)=0.
y'(0)=1.
18) y+2y+17y=0,
y(0)=0.
y'(0)=12.
19) y"-4y+5y=0,
y(0)=1,
y'(0)=2.
20) 9y-6y+y=0,
(0)-3,
y'(0)=1.
21) -2y+10y=0,
y(0)=3,
y'(0)=3.
22) 4y-4y+37y=0,
y(0)=3.
y'(0)=1.5
23) 4y-8y+5y=0,
y(0)=0,
y'(0)=1.
24)
++1.25y-0,
y(0)=1,
y'(0)=-0.5
25) y 2 cos(r).
y(0)=2.
y'(0) = 0.
26)
-4y+3y-0,
y(0)=3,
y(0) 7.
27) y+2y+y=e
y(0)=0.
y'(0)=0.
28) y+2y-3y=10sinh(27),
y(0)=0.
y'(0)=4.
29)…
Chapter 20 Solutions
Fundamentals of Thermal-Fluid Sciences
Ch. 20 - Prob. 1PCh. 20 - In which mode of heat transfer is the convection...Ch. 20 - Consider a hot boiled egg in a spacecraft that is...Ch. 20 - Prob. 4PCh. 20 - Prob. 5PCh. 20 - Prob. 6PCh. 20 - Prob. 7PCh. 20 - Prob. 8PCh. 20 - Prob. 9PCh. 20 - The density of liquid water can be correlated as...
Ch. 20 - A 10 cm × 10 cm plate has a constant surface...Ch. 20 - Prob. 12PCh. 20 - Prob. 13PCh. 20 - Prob. 14PCh. 20 - Prob. 15PCh. 20 - A 0.2-m-long and 25-mm-thick vertical plate (k =...Ch. 20 - A 0.2-m-long and 25-mm-thick vertical plate (k =...Ch. 20 - A 0.5-m-long thin vertical plate is subjected to...Ch. 20 - Prob. 21PCh. 20 - Prob. 22PCh. 20 - Prob. 24PCh. 20 - Consider a 2-ft × 2-ft thin square plate in a room...Ch. 20 - Prob. 27PCh. 20 - A 50-cm × 50-cm circuit board that contains 121...Ch. 20 - Prob. 29PCh. 20 - Prob. 30PCh. 20 - Prob. 32PCh. 20 - Consider a thin 16-cm-long and 20-cm-wide...Ch. 20 - Prob. 34PCh. 20 - Prob. 35PCh. 20 - Prob. 36PCh. 20 - Prob. 37PCh. 20 - Flue gases from an incinerator are released to...Ch. 20 - In a plant that manufactures canned aerosol...Ch. 20 - Reconsider Prob. 20–39. In order to reduce the...Ch. 20 - Prob. 41PCh. 20 - Prob. 42PCh. 20 - Prob. 43PCh. 20 - Prob. 44PCh. 20 - A 10-m-long section of a 6-cm-diameter horizontal...Ch. 20 - Prob. 46PCh. 20 - Prob. 47PCh. 20 - Prob. 48PCh. 20 - Prob. 49PCh. 20 - Prob. 50PCh. 20 - Prob. 52PCh. 20 - Prob. 53PCh. 20 - Prob. 54PCh. 20 - Prob. 55PCh. 20 - Prob. 57PCh. 20 - Prob. 58PCh. 20 - Prob. 59PCh. 20 - Prob. 60PCh. 20 - Prob. 61PCh. 20 - Prob. 62PCh. 20 - Prob. 63PCh. 20 - Prob. 64PCh. 20 - Prob. 65PCh. 20 - Prob. 66PCh. 20 - Prob. 67PCh. 20 - Prob. 68PCh. 20 - Prob. 69PCh. 20 - Prob. 70PCh. 20 - Prob. 71PCh. 20 - Prob. 72PCh. 20 - Prob. 73PCh. 20 - Prob. 75PCh. 20 - Prob. 77PCh. 20 - Prob. 78PCh. 20 - Prob. 79PCh. 20 - Prob. 81PCh. 20 - An electric resistance space heater is designed...Ch. 20 - Prob. 83RQCh. 20 - A plate (0.5 m × 0.5 m) is inclined at an angle of...Ch. 20 - A group of 25 power transistors, dissipating 1.5 W...Ch. 20 - Prob. 86RQCh. 20 - Prob. 87RQCh. 20 - Consider a flat-plate solar collector placed...Ch. 20 - Prob. 89RQCh. 20 - Prob. 90RQCh. 20 - Prob. 91RQCh. 20 - Prob. 92RQCh. 20 - Prob. 93RQCh. 20 - Prob. 94RQCh. 20 - Prob. 95RQCh. 20 - Prob. 96RQCh. 20 - Prob. 97RQCh. 20 - Prob. 98RQCh. 20 - Prob. 99RQCh. 20 - Prob. 100RQCh. 20 - Prob. 101RQCh. 20 - A solar collector consists of a horizontal copper...Ch. 20 - Prob. 103RQCh. 20 - Prob. 104RQ
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