Microsoft Word - Cengel and Boles TOC _2-03-05_.doc

Chapter 1 | 45

unknown density is poured into one side, and the water level

rises a certain amount on the other side to compensate for

this effect. Based on the final fluid heights shown on the fig-

ure, determine the density of the fluid added. Assume the

liquid does not mix with water.

1–76 Consider a double-fluid manometer attached to an air

pipe shown in Fig. P1–76. If the specific gravity of one fluid

is 13.55, determine the specific gravity of the other fluid for

the indicated absolute pressure of air. Take the atmospheric

pressure to be 100 kPa. Answer: 5.0

1–78 A multifluid container is connected to a U-tube, as

shown in Fig. P1–78. For the given specific gravities and

fluid column heights, determine the gage pressure at A. Also

determine the height of a mercury column that would create

the same pressure at A. Answers:0.471 kPa, 0.353 cm

SG 2

Air

P = 76 kPa

22 cm

40 cm

SG 1 = 13.55

FIGURE P1–76

Mercury

SG = 13.56

Water

Air

Area, A 1

Area, A 2

Brine

pipe

SG = 1.1

FIGURE P1–77

1–77 Consider the system shown in Fig. P1–77. If a change

of 0.7 kPa in the pressure of air causes the brine–mercury

interface in the right column to drop by 5 mm in the brine

level in the right column while the pressure in the brine pipe

remains constant, determine the ratio of A 2 /A 1.

Solving Engineering Problems and EES

1–79C What is the value of the engineering software pack-

ages in (a) engineering education and (b) engineering prac-

tice?

1–80 Determine a positive real root of this equation

using EES:

1–81 Solve this system of two equations with two

unknowns using EES:

1–82 Solve this system of three equations with three

unknowns using EES:

1–83 Solve this system of three equations with three

unknowns using EES:

x
yz 2

x 3 y0.5
xz 2

x^2 yz 1

xy
 2 z 8

3 x^2 
 2 yz
 2

2 xy
z 5

3 xy
y3.5

x^3 y^2 7.75

2 x^3  10 x0.5 3 x 3

70 cm Oil

SG = 0.90

Water

Glycerin

SG = 1.26

30 cm

20 cm

15 cm

90 cm

A

FIGURE P1–78

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