fluid_mechanics

ANS-4
Answers to Selected Even-Numbered Homework Problems
6.102 v u R 2 vr
6.104 V 1.10 10 2 ms
rv
6.106 v u
11 r i2 r 2 o 2 c 1 r i 2
r d 2
¢p
6.108 lbft 2 per ft
/ 33.1
6.110 1a2 42.6%; 1b2 21.7%
Chapter 7
7.6 1a2 103 ms; 1b2 444 ms
7.8 k r 3 pi terms
7.10 1a2 p is halved; 1b2 p is doubled
7.12 pD 1 1V2 1D 2 D 1 , D 1 V2
7.14 p1D 5 3 2 1QD 3 2
7.16 p1D 2 2 2 1QD 3 2
7.18 h/ f1s/ 2 gr2
7.20 hD 1D 2 2
7.22 p 1D 2 1for a given velocity2
7.24 dD 1VD, V
2 D2
7.26 1a2 VD 2r f1bd, dD2; 1b2 V
22bprdD 2
7.30 p1V 2 2 0.505 1Dd2 3.99
7.32 1a2 Hb f1hb, /b2;
1b2 Hb 0.0833 1hb2 1.00
7.34 1a2 n 12; 1b2 Yes
7.38 Colder
7.40 0.963 ft s
7.42 9.49 m
s
7.44 s ms 4.44 10 3
7.46 1170 kmhr
7.48 187 mph
7.50 hd f1Hd, g sg f , m f g 1 2
1g f d 32 22
7.52 1a2 400 kmhr; 1b2 170 N
7.54 26.4 lb
7.56 1a2 d m D m dD, m pm p , g m d 3 m 2 m 2 m
gd 3 2 2 , V c D m V cm D m m ; 1b2 V cm V c
0.707
7.58 1a2 drV 2 D 2 f1dD2; 1b2 31.1 lb
7.60 1a2 12 ms; 1b2 900 N
7.62 0.0647 to 0.0971
7.68 1a2 400 N; 1b2 7222 W
7.70 1a2 V/ 2 Q f1/ i/, Q 2 / 5 g, rQ/m2; no
1b2 0.410 gpm; 2.46 in.
7.72 1a2 nDV 1VDn2; 1b2 Yes; 1c2 7.54 fts
7.74 1a2 V m U m VU, V m D mn sm VDn s ,
V m2 g m D m V 2 g D, 1r r s 2 m r m
1r r s 2r; 1b2 no
7.76 1a2 prV 2 f1// ; 1b2 0.333 ft; 1c2 p 1VV 2 i 2
m 2
p m , No
7.78 1rvh 2 m2 0u*0t* 0 2 u*0y* 2
7.80 0v z *0t* p 1
rR 3 1/ 2 m2 0 2 v z *0r* 2
11r*2 0v z *0r*
Chapter 8
8.2 1.0 ft
8.4 blue and yellow streams; green
8.6 17.7 ft
8.8 0.0883 m
8.10 1a2 8.93 10 4 ; 1b2 8.93 10 8
8.12 V max 2 ms,
V 1 ms, Q 1.3
10 3 m 3 s
8.14 0.15 lb ft 2 , 0.06 lbft 2 , 0 lbft 2
8.16 from 1b2 to 1a2
8.18 0.354 D
8.20 3.43 m, 166 kPa
8.22 1a2 12.42 kPa; 1b2 15.85 kPa
8.24 2.01 fts
8.26 D
8.28 18.5 m
8.30 8.88 10 8 m 3 s
8.32 26,300, turbulent
8.38 0.00243 ft
8.42 0.65 Pa m
8.44 0.02 ft ft
8.46 water out if V 5 ms; air in if V 0.5 ms
8.48 1b2
8.50 smaller pipe
8.52 1a2 34.5 lbft 2 ; 1a2 908 lbft 2
8.54 21.0
8.58 8.15 ft
8.60 1a2 23.8 ft
8.62 133 kPa; 39.7 kPa from losses and 93.0 kPa from
change in kinetic energy
8.64 13.0
8.66 0.223 lbft 2
8.68 9
8.70 disagree
8.72 aspect ratio equal to 4
8.74 0.188 m
8.76
8.78
0.899 lbft 2
1a2 135 ft; 1b2 137 ft
8.80 No
8.82 50.0 m
8.84 0.325 psi
8.86 16.5 ft
8.90 379 kW
8.94
8.98
0.06 ft 3 s
5.73 fts
8.100 0.442 ft
8.102 0.535 ft
8.104 0.031 m by 0.053 m
8.108 0.0746 cfs; 0.339 cfs
8.110 0.662 ft
8.112 0.0284 m 3 s; 0.0143 m 3 s; 0.0141 m 3 s
8.116 24.9 psi
8.118 64.8 kPa
8.120 0.528 ft 3 s
8.122 0.115 ft 3 s
8.124 0.0936 ft 3 s
Chapter 9
9.2 1.1
9.4 3.45 kN, 0.560 kN; 3.47 kN, 0.427 kN