Fox and McDonald's Introduction to Fluid Mechanics
9th Edition
ISBN: 9781118912652
Author: Philip J. Pritchard, John W. Mitchell
Publisher: WILEY
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Textbook Question
Chapter 1, Problem 12P
The English perfected the longbow as a weapon after the Medieval period. In the hands of a skilled archer, the longbow was reputed to be accurate at ranges to 100 m or more. If the maximum altitude of an arrow is less than h = 10 m while traveling to a target 100 m away from the archer, and neglecting air resistance, estimate the speed and angle at which the arrow must leave the bow. Plot the required release speed and angle as a function of height h.
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PRACTICE II
Use the worked example above to help you solve this problem. A rocket has a total mass of 1.04 x 105 kg
and a burnout mass of 1.07 x 104 kg, including engines, shell and payload. The rocket blasts off from
Earth and exhausts all its fuel in 3.86 min, burning the fuel at a steady rate with an exhaust velocity of ve
= 4.16 x 10³ m/s.
(a) If air friction and gravity are neglected, what is the speed of the rocket at burnout?
m/s
(b) What thrust does the engine develop at liftoff?
N
(c) What is the initial acceleration of the rocket if gravity is not neglected?
m/s²
(d) Estimate the speed at burnout if gravity isn't neglected.
m/s
EXERCISE
A spaceship with a mass of 4.90 x 104 kg is traveling at 5.71 x 10³ m/s relative to a space station. What
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exhaust velocity of 4.73 x 10³ m/s.
kg
HINTS:
GETTING STARTED I I'M STUCK!
Chapter 1 Solutions
Fox and McDonald's Introduction to Fluid Mechanics
Ch. 1 - A number of common substances are Some of these...Ch. 1 - Give a word statement of each of the five basic...Ch. 1 - The barrel of a bicycle tire pump becomes quite...Ch. 1 - Very small particles moving in fluids are known to...Ch. 1 - In a combustion process, gasoline particles are to...Ch. 1 - In a pollution control experiment, minute solid...Ch. 1 - A rocket payload with a weight on earth of 2000 lb...Ch. 1 - A cubic metre of air at 101 kPa absolute and 15C...Ch. 1 - Calculate the specific weight, specific volume,...Ch. 1 - For Problem 1.6, find the distance the particles...
Ch. 1 - A sky diver with a mass of 70 kg jumps from an...Ch. 1 - The English perfected the longbow as a weapon...Ch. 1 - For each quantity listed, indicate dimensions...Ch. 1 - The density of a sample of sea water is 1.99...Ch. 1 - A pump is rated at 50 hp. What is the rating in kW...Ch. 1 - A fluid occupying 3.2m3 has a mass of 4 Mg....Ch. 1 - If a power plant is rated at 2000 MW output and...Ch. 1 - For each quantity listed, indicate dimensions...Ch. 1 - Derive the following conversion factors: (a)...Ch. 1 - Express the following in SI units: (a) 5 acreft...Ch. 1 - Express the following in SI units: (a) 100...Ch. 1 - Express the following in BG units: (a) 50 m2 (b)...Ch. 1 - While youre waiting for the ribs to cook, you muse...Ch. 1 - Derive the following conversion factors: (a)...Ch. 1 - The kilogram force is commonly used in Europe as a...Ch. 1 - From thermodynamics, we know that the coefficient...Ch. 1 - The maximum theoretical flow rate (slug/s) through...Ch. 1 - The mean free path of a molecule of gas is the...Ch. 1 - A container weighs 3.5 lbf when empty. When filled...Ch. 1 - A parameter that is often used in describing pump...Ch. 1 - Calculate the density of standard air in a...Ch. 1 - The mass of the standard American golf ball is...Ch. 1 - A can of pet food has the following internal...Ch. 1 - The mass flow rate in a water flow system...Ch. 1 - The mass flow rate of water in a tube is measured...Ch. 1 - The mass of the standard British golf ball is 45.9...Ch. 1 - From Appendix A, the viscosity (Ns/m2) of water at...Ch. 1 - An enthusiast magazine publishes data from its...Ch. 1 - The height of a building may be estimated by...Ch. 1 - An American golf ball is described in Problem 1.32...
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