Fluid Mechanics
8th Edition
ISBN: 9780073398273
Author: Frank M. White
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 1, Problem 1.5P
The mean free path of a gas, l, is defined as the average distance traveled by molecules between collisions. A proposed formula for estimating t of an ideal gas is
What are the dimensions of the constant 1.26? Use the formula to estimate the mean free path of air at 20°C and 7 kPa. Would you consider air rarefied at this condition?
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Students have asked these similar questions
A gas at 20°C may be considered rarefied, deviating from the continuum concept, when it
contains less than 101
molecules per cubic millimeter. If Avogadro's number is 6.029 E23
molecules per mole, what absolute pressure (in Pa) for air does this represent?
Consider the following equation. All three of the terms in parentheses are dimensionless groups. Because kC is difficult to determine directly, the other variables are measured and kC is calculated from the given equation.
What is the estimated value of kC? What are the units of kC? Show your work. The following values were measured: D = 8.0 mm, DAB = 0.475 cm2/s, μ = 1.12 x 10–3 N-s/m2, ρ = 1.00 x 10–3 g/cm3, v = 15.0 m/s.
Note: Given Equation attached below
How much heat is absorbed by a 27.0 g sample of water in going from liquid at 38.2 °C to steam
at 119 °C and a pressure of 1.00 atm? Use the data in the following table. Express your answer
in kilojoules. Pay attention to units!
Some Thermal Properties of Water
Property
Specific heat (J/g °C)
Solid
Liquid
Gas
AHfusion (kJ/mol; at 0 °C)
A Hvaporization (kJ/mol; at 100 °C)
A Hsublimation (kJ/mol)
Melting point (°C)
Boiling point (°C)
Answer:
Value
2.07
4.18
2.01
6.01
40.6
50.9
0
100
Chapter 1 Solutions
Fluid Mechanics
Ch. 1 - Prob. 1.1PCh. 1 - Table A.6 lists the density of the standard...Ch. 1 - For the triangular element in Fig, P1.3,show that...Ch. 1 - Sand, and other granular materials, appear to...Ch. 1 - The mean free path of a gas, l, is defined as the...Ch. 1 - Henri Darcy, a French engineer, proposed that the...Ch. 1 - Convert the following inappropriate quantities...Ch. 1 - Suppose we know little about the strength of...Ch. 1 - A hemispherical container, 26 inches in diameter,...Ch. 1 - The Stokes-Oseen formula [33] for drag force F on...
Ch. 1 - P1.11 In English Engineering units, the specific...Ch. 1 - For low-speed (laminar) steady flow through a...Ch. 1 - The efficiency ? of a pump is defined as the...Ch. 1 - Figure P1.14 shows the flow of water over a dam....Ch. 1 - The height H that fluid rises in a liquid...Ch. 1 - Algebraic equations such as Bernoulli's relation,...Ch. 1 - The Hazen-Williams hydraulics formula for volume...Ch. 1 - For small particles at low velocities, the first...Ch. 1 - In his study of the circular hydraulic jump formed...Ch. 1 - Books on porous media and atomization claim that...Ch. 1 - Aeronautical engineers measure the pitching moment...Ch. 1 - Prob. 1.22PCh. 1 - During World War II, Sir Geoffrey Taylor, a...Ch. 1 - Air, assumed to be an ideal gas with k = 1.40,...Ch. 1 - On a summer day in Narragansett, Rhode Island, the...Ch. 1 - When we in the United States say a car's tire is...Ch. 1 - Prob. 1.27PCh. 1 - Wet atmospheric air at 100 percent relative...Ch. 1 - Prob. 1.29PCh. 1 - P1.30 Repeat Prob. 1.29 if the tank is filled with...Ch. 1 - Prob. 1.31PCh. 1 - Prob. 1.32PCh. 1 - A tank contai as 9 kg of CO2at 20°C and 2.0 MPa....Ch. 1 - Consider steam at the following state near the...Ch. 1 - In Table A.4, most common gases (air, nitrogen,...Ch. 1 - Prob. 1.36PCh. 1 - A near-ideal gas has a molecular weight of 44 and...Ch. 1 - In Fig. 1.7, if the fluid is glycerin at 20°C and...Ch. 1 - Prob. 1.39PCh. 1 - Glycerin at 20°C fills the space between a hollow...Ch. 1 - An aluminum cylinder weighing 30 N, 6 cm in...Ch. 1 - Prob. 1.42PCh. 1 - Prob. 1.43PCh. 1 - One type of viscometer is simply a long capillary...Ch. 1 - A block of weight W slides down an inclined plane...Ch. 1 - A simple and popular model for two nonnewtonian...Ch. 1 - Data for the apparent viscosity of average human...Ch. 1 - A thin plate is separated from two fixed plates by...Ch. 1 - An amazing number of commercial and laboratory...Ch. 1 - Prob. 1.50PCh. 1 - Prob. 1.51PCh. 1 - The belt in Fig. P1.52 moves at a steady velocity...Ch. 1 - A solid tune of angle 2 , base r0, and density...Ch. 1 - A disk of radius R rotates at an angular velocity ...Ch. 1 - A block of weight W is being pulled over a table...Ch. 1 - The device in Fig. P1.56 is called a cone-plate...Ch. 1 - Extend the steady flow between a fixed lower plate...Ch. 1 - The laminar pipe flow example of Prob. 1.12 can be...Ch. 1 - A solid cylinder of diameter D, length L, and...Ch. 1 - Prob. 1.60PCh. 1 - Prob. 1.61PCh. 1 - P1.62 The hydrogen bubbles that produced the...Ch. 1 - Derive Eq. (1.33) by making a force balance on the...Ch. 1 - Pressure in a water container can be measured by...Ch. 1 - The system in Fig. P1.65 is used to calculate the...Ch. 1 - Prob. 1.66PCh. 1 - Prob. 1.67PCh. 1 - Prob. 1.68PCh. 1 - A solid cylindrical needle of diameter d, length...Ch. 1 - Derive an expression for the capillary height...Ch. 1 - A soap bubble of diameter D1coalesces with another...Ch. 1 - Early mountaineers boiled water to estimate their...Ch. 1 - A small submersible moves al velocity V, in fresh...Ch. 1 - Oil, with a vapor pressure of 20 kPa, is delivered...Ch. 1 - An airplane flies at 555 mi/h. At what altitude in...Ch. 1 - Prob. 1.76PCh. 1 - Prob. 1.77PCh. 1 - P1.78 Sir Isaac Newton measured the speed of sound...Ch. 1 - Prob. 1.79PCh. 1 - Prob. 1.80PCh. 1 - Use Eq. (1.39) to find and sketch the streamlines...Ch. 1 - P1.82 A velocity field is given by u = V cos, v =...Ch. 1 - Prob. 1.83PCh. 1 - In the early 1900s, the British chemist Sir Cyril...Ch. 1 - Prob. 1.85PCh. 1 - A right circular cylinder volume v is to be...Ch. 1 - The absolute viscosity of a fluid is primarily a...Ch. 1 - Prob. 1.2FEEPCh. 1 - Helium has a molecular weight of 4.003. What is...Ch. 1 - An oil has a kinematic viscosity of 1.25 E-4 m2/s...Ch. 1 - Prob. 1.5FEEPCh. 1 - Prob. 1.6FEEPCh. 1 - FE1.7 Two parallel plates, one moving at 4 m/s...Ch. 1 - Prob. 1.8FEEPCh. 1 - A certain water flow at 20°C has a critical...Ch. 1 - Prob. 1.10FEEPCh. 1 - Sometimes we can develop equations and solve...Ch. 1 - When a person ice skates, the surface of the ice...Ch. 1 - Two thin flat plates, tilted at an angle a, are...Ch. 1 - Oil of viscosity and density drains steadily...Ch. 1 - Prob. 1.5CPCh. 1 - Prob. 1.6CPCh. 1 - Prob. 1.7CPCh. 1 -
C1.8 A mechanical device that uses the rotating...Ch. 1 - Prob. 1.9CPCh. 1 - A popular gravity-driven instrument is the...Ch. 1 - Mott [Ref. 49, p. 38] discusses a simple...Ch. 1 - A solid aluminum disk (SG = 2.7) is 2 in in...
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