Fox And Mcdonald's Introduction To Fluid Mechanics
9th Edition
ISBN: 9781118921876
Author: Pritchard, Philip J.; Leylegian, John C.; Bhaskaran, Rajesh
Publisher: WILEY
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 7, Problem 36P
Spin plays an important role in the flight trajectory of golf, ping-pong, and tennis balls. Therefore, it is important to know the rate at which spin decreases for a ball in flight. The aerodynamic torque, T, acting on a ball in flight, is thought to depend on flight speed, V, air density, ρ, air viscosity, μ, ball diameter, D, spin rate (angular speed), ω, and diameter of the dimples on the ball, d. Determine the dimensionless parameters that result.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
The power P required to turn a ship will depend on its velocity V , its length L, its width B, the water density ρ and viscosity µ, the rate of turning ω, and the acceleration due to gravity g. (a) Express the non-dimensional power in terms of its dependence on the other non-dimensional groups. Show all your working. (b) It is proposed to test a model ship at 1/100th scale. What scaled velocity, kinematic viscosity, and turning rate would be required for the test to be dynamically similar? Do you foresee any possible difficulties in performing this test?
Wind blows and pasts a banner causes it to flutter. The fluttering frequency f is a function of the wind speed V, the air density ρ, the acceleration of gravity g, the length of the banner L and the “area density” of the flag material ρA (with dimensions of ML-2 ). In order to estimate the flutter frequency of a large banner with L = 40 ft in a V = 30 ft/s wind, a small banner with L = 4 ft is to be tested in a wind tunnel.
(a) What is the area density of the small banner when the large banner has area density of 0.006 slugs/ft2?
(b) What should the wind tunnel velocity be to test the small model?
(c) It has been shown that the small banner flutters at 6 s-1 when the same area density and wind tunnel velocity are used in parts (a) and (b). In this case, what is the fluttering frequency of the large banner?
The propeller on Don Karnage's airplane can be modeled as three identical thin rods of uniform density extending radially from the rotational axis of the propeller. To take off, the propeller must accelerate from rest to 633 rpm in 4 s. If the length and mass of each rod are 0.872 m and 3.11 kg, what must be the magnitude of torque in N*m) necessary to accelerate the propeller?
Explain how you solved the problem involving something undergoing angular acceleration Be sure to state what your known and unknown quantities are, what concepts were applied, and what equations were used!
Chapter 7 Solutions
Fox And Mcdonald's Introduction To Fluid Mechanics
Ch. 7 - The slope of the free surface of a steady wave in...Ch. 7 - One-dimensional unsteady flow in a thin liquid...Ch. 7 - In atmospheric studies the motion of the earths...Ch. 7 - Fluid fills the space between two parallel plates....Ch. 7 - By using order of magnitude analysis, the...Ch. 7 - Consider a disk of radius R rotating in an...Ch. 7 - An unsteady, two-dimensional, compressible,...Ch. 7 - Experiments show that the pressure drop for flow...Ch. 7 - At very low speeds, the drag on an object is...Ch. 7 - We saw in Chapter 3 that the buoyant force, FB, on...
Ch. 7 - Assume that the velocity acquired by a body...Ch. 7 - Derive by dimensional analysis an expression for...Ch. 7 - The speed of shallow water waves in the ocean...Ch. 7 - The speed, V, of a free-surface wave in shallow...Ch. 7 - The boundary-layer thickness, , on a smooth flat...Ch. 7 - The speed, V, of a free-surface gravity wave in...Ch. 7 - Derive an expression for the velocity of very...Ch. 7 - Derive an expression for the axial thrust exerted...Ch. 7 - Derive an expression for drag force on a smooth...Ch. 7 - The energy released during an explosion, E, is a...Ch. 7 - Measurements of the liquid height upstream from an...Ch. 7 - The load-carrying capacity, W, of a journal...Ch. 7 - Derive an expression for the drag force on a...Ch. 7 - A circular disk of diameter d and of negligible...Ch. 7 - Two cylinders are concentric, the outer one fixed...Ch. 7 - The time, t, for oil to drain out of a viscosity...Ch. 7 - You are asked to find a set of dimensionless...Ch. 7 - A continuous belt moving vertically through a bath...Ch. 7 - Derive an expression for the frictional torque...Ch. 7 - Tests on the established flow of six different...Ch. 7 - The power, P, required to drive a fan is believed...Ch. 7 - The sketch shows an air jet discharging...Ch. 7 - The diameter, d, of bubbles produced by a...Ch. 7 - Choked-flow nozzles are often used to meter the...Ch. 7 - A large tank of liquid under pressure is drained...Ch. 7 - Spin plays an important role in the flight...Ch. 7 - The power loss, P, in a journal bearing depends on...Ch. 7 - The thrust of a marine propeller is to be measured...Ch. 7 - The rate dT/dt at which the temperature T at the...Ch. 7 - When a valve is closed suddenly in a pipe with...Ch. 7 - An airship is to operate at 20 m/s in air at...Ch. 7 - An airplane wing of 3 m chord length moves through...Ch. 7 - A flat plate 1.5 m long and 0.3 m wide is towed at...Ch. 7 - This 1:12 pump model using water at 15C simulates...Ch. 7 - An ocean-going vessel is to be powered by a...Ch. 7 - On a cruise ship, passengers complain about the...Ch. 7 - A 1:3 scale model of a torpedo is tested in a wind...Ch. 7 - A flow rate of 0:18 m3/s of water at 20C...Ch. 7 - A force of 9 N is required to tow a 1:50 ship...Ch. 7 - An airplane wing, with chord length of 1.5 m and...Ch. 7 - A water pump with impeller diameter of 24 in. is...Ch. 7 - A model hydrofoil is to be tested at 1:20 scale....Ch. 7 - A ship 120 m long moves through freshwater at 15C...Ch. 7 - A 1:30 scale model of a cavitating overflow...Ch. 7 - In some speed ranges, vortices are shed from the...Ch. 7 - A 1:8 scale model of a tractor-trailer rig is...Ch. 7 - On a cruise ship, passengers complain about the...Ch. 7 - When a sphere of 0.25 mm diameter and specific...Ch. 7 - The flow about a 150 mm artillery projectile which...Ch. 7 - Your favorite professor likes mountain climbing,...Ch. 7 - A 1:50-scale model of a submarine is to be tested...Ch. 7 - Consider water flow around a circular cylinder, of...Ch. 7 - A 1:10 scale model of a tractor-trailer rig is...Ch. 7 - The power, P, required to drive a fan is assumed...Ch. 7 - Over a certain range of air speeds, V, the lift,...Ch. 7 - The pressure rise, p, of a liquid flowing steadily...Ch. 7 - An axial-flow pump is required to deliver 0.75...Ch. 7 - A model propeller 1 m in diameter is tested in a...Ch. 7 - Consider Problem 7.38. Experience shows that for...Ch. 7 - Closed-circuit wind tunnels can produce higher...Ch. 7 - A 1:16 model of a bus is tested in a wind tunnel...Ch. 7 - The propagation speed of small-amplitude surface...
Additional Engineering Textbook Solutions
Find more solutions based on key concepts
Two couples act on the beam as shown. If F = 150 lb, determine the resultant couple moment.
INTERNATIONAL EDITION---Engineering Mechanics: Statics, 14th edition (SI unit)
Why is the study of database technology important?
Database Concepts (8th Edition)
Write and test a Python script that reads in a character string and an integer, and outputs the character strin...
Computer Science: An Overview (13th Edition) (What's New in Computer Science)
Consider the following fragment of code: What is displayed if x is a. 4; b. 5; c. 6; d. 9; e. 10; f. 11
Java: An Introduction to Problem Solving and Programming (8th Edition)
What is the output of the following program? #include iostream using namespace std; // Function prototype void ...
Starting Out with C++: Early Objects (9th Edition)
The current source in the circuit shown generates the current pulse
Find (a) v (0); (b) the instant of time gr...
Electric Circuits. (11th Edition)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- The power P required to drive a propeller is known to depend on the diameter of the propeller D, the density of fluid ρ, the speed of sound a, the angular velocity of the propeller ω, the freestream velocity V , and the viscosity of the fluid µ. (a) How many dimensionless groups characterize this problem? (b) If the effects of viscosity are neglected, and if the speed of sound is not an important variable, express the relationship between power and the other variables in nondimensional form. (c) A one-half scale model of a propeller is built, and it uses Pm horsepower when running at a speed ωm. If the full-scale propeller in the same fluid runs at ωm/2, what is its power consumption in terms of Pm if the functional dependence found in part (b) holds? What freestream velocity should be used for the model test?arrow_forwardThe drag FD of the golf ball is affected by the speed V of the ball, the diameter d of the ball, the depth , of the dimple, the radius r of the dimple, the density C of the dimple, the density of air, and the viscosity µ. Perform a dimensional analysis to represent the drag of the golf ball as a function of these variables.arrow_forwardThe aerodynamic drag of a new sports car is to be predicted at a speed of 60.0 mi/h at an air temperature of 25°C. Automotive engineers build a one-third scale model of the car to test in a wind tunnel. The temperature of the wind tunnel air is also 25°C. The drag force is measured with a drag balance, and the moving belt is used to simulate the moving ground (from the car’s frame of reference). Determine how fast the engineers should run the wind tunnel to achieve similarity between the model and the prototype.arrow_forward
- The aerodynamic drag of a new sports car is to be predicted at a speed of 60.0 mi/h at an air temperature of 25°C. Automotive engineers build a one-third scale model of the car to test in a wind tunnel. The temperature of the wind tunnel air is also 25°C. The drag force is measured with a drag balance, and the moving belt is used to simulate the moving ground (from the car’s frame of reference). Determine how fast the engineers should run the wind tunnel to achieve similarity between the model and the prototype.arrow_forwardSolve it correctly please.I will rate accordingly. Plarrow_forwardWith reference to the attached example. Apply dimensinal analysis to show that all values/units used are homogeneous.arrow_forward
- 5.13 The torque due to the frictional resistance of the oil film between a rotating shaft and its bearing is found to be dependent on the force F normal to the shaft, the speed of rotation N of the shaft, the dynamic viscosity of the oil, and the shaft diameter D. Establish a correlation among these variables by using dimensional analysis.arrow_forwardA Jello desert resting on a plate is starts wiggling when it is sheared to the side 0.5 cm as is set on the table. The desert is a rectangular prism with a square face 25.0-cm on a side and a height of 12.0 cm. A quick Google search reveals that the density of Jello is 1140 kg/m3 with shear modulus of 530 N/m2. What is its rate of oscillation? If the energy of oscillation is dissipated at the rate of 5.00 x 10-5 J per second how long will the block wiggle?arrow_forwardThe plate of a record player with a moment of inertia of 0:015 kg m2 rotates freely at 33 rpm. If you slowly drop a 180-gram vinyl disc with a 30:48 cm diameter on the board, what will be the new angular speed? (N.B. In real life, the turntable motor forces the speed to always remain 33 rpm. In this problem, we act as if the engine did not exist. )arrow_forward
- Let's say that the semiempirical binding energy formula is Eb= aA-bA^2/3 - s(N-Z)^2/A -dZ^2/A^1/3 where a,b,s,d are constants. Imagine that you are in a different universe where there are 3 types of nucleons with spin equal to 1/2 and electric charges equal to +1, -1 and 0. Mass similar to that of a proton. Forces are similar to those of our universe. i) How do equations change for A and Z as a function of N+, N-, No and what is the semiempirical equation for the binding energy as a function of A, Z, and No? ii) At what Z and No do we have the maximum and minimum binding energy for every A? iii) When do we have stable nuclei under beta (β) decay? If "alpha particle" in this situation has N+ = N- = No = 2, what does apply for alpha (α) decay? iv) What does apply for nuclear fission and finally, how would life be in this situation?arrow_forwardDevelop the Weber number by starting with estimates for the inertia and surface tension forces. p is density, Vis velocity, I is length, and o is a surface temsion. X Your answer is incorrect. Inertia force ~ O pV²1 O pVI 0 pv ²1²arrow_forwardQ1: If an air stream flowing at velocity (U) pasta body of length (L) causes a drag force (F) on the body which depends only upon U, L, and fluid viscosity μ. Formulate the suitable dimensionless parameter of the air drag force.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning
Principles of Heat Transfer (Activate Learning wi...
Mechanical Engineering
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Cengage Learning
Properties of Fluids: The Basics; Author: Swanson Flo;https://www.youtube.com/watch?v=TgD3nEO1iCA;License: Standard YouTube License, CC-BY
Fluid Mechanics-Lecture-1_Introduction & Basic Concepts; Author: OOkul - UPSC & SSC Exams;https://www.youtube.com/watch?v=6bZodDnmE0o;License: Standard Youtube License