Fluid Mechanics
8th Edition
ISBN: 9780073398273
Author: Frank M. White
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 7, Problem 7.63P
For those who think electric cars are sissy, Keio University in Japan has tested a 22-ft-long prototype whose eight electric motors generate a total of 590 horsepower. The “Kaz” cruises at 180 mi/h (see Popular Science, August 2001, p. 15). If the drag coefficient is 0.35 and the frontal area is 26 ft2. What percentage of this power is expended against sea-level air drag?
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(a) A luxury sports car has a frontal area of 23.1 ft and a 0.24 coefficient of drag at 80 mph. How much power must the engine produce just to overcome the air drag?
(Express your answer using three significant figures.)
P =
hp
(b) A sport-utility vehicle has Cp = 0.45 at 80 mph and a slightly larger frontal area of 28.3 ft. How much power must the engine produce just to overcome the air drag?
(Express your answer using three significant figures.)
P =[
hp
Current Attempt in Progress
In the 1930s, the U.S. Navy operated dirigibles. The largest was the U.S.S. Akron with a length of 785 ft and a maximum diameter of
132 ft. Its maximum speed was 84 mph (123.2 ft/sec). Moving at top speed at 10,000 ft standard atmosphere, estimate the power
required in horsepower to overcome the friction drag. Disregard effects of fins and other protrusions. Assume the surface of the
dirigible is smooth and the friction drag is that over a flat plate. (Hint: "unwrap" the outer surface of the ship.)
W =
hp
A 5,000 lb airplane with wing area of 250 sq. ft and power available of 450 hp is at sea level flight
standard condition. The airplane drag-to-lift relation is close to Co = 0.025 + 0.048 CL². What is the rate
of climb (in feet per minute) at a flight speed of 180 miles per hour?
Chapter 7 Solutions
Fluid Mechanics
Ch. 7 - Prob. 7.1PCh. 7 - A gas at 20°C and 1 atm flows at 6 ft/s past a...Ch. 7 - Prob. 7.3PCh. 7 - Prob. 7.4PCh. 7 - SAE 30 oil at 20°C flows at 1.8 ft3/s from a...Ch. 7 - Prob. 7.6PCh. 7 - P7.7 Air at 20°C and 1 atm enters a 40-cm-square...Ch. 7 - P7.8 Air, p = 1.2 kg/m3 and E-5 kg/(m .s), flows...Ch. 7 - P7.9 Repeat the flat-plate momentum analysis of...Ch. 7 - Repeat Prob. P7.9, using a trigonometric profile...
Ch. 7 - Prob. 7.11PCh. 7 - Prob. 7.12PCh. 7 - Prob. 7.13PCh. 7 - Prob. 7.14PCh. 7 - Prob. 7.15PCh. 7 - A thin flat plate 55 by 110 cm is immersed in a...Ch. 7 - Consider laminar flow past a sharp flat plate of...Ch. 7 - Air at 20°C and 1 atm flows at 5 m/s past a flat...Ch. 7 - Prob. 7.19PCh. 7 - Air at 20°C and I atm flows at 20 m/s past the...Ch. 7 - Prob. 7.21PCh. 7 - Prob. 7.22PCh. 7 - Prob. 7.23PCh. 7 - Prob. 7.24PCh. 7 - Prob. 7.25PCh. 7 - P7.26 Consider laminar boundary layer flow past...Ch. 7 - Prob. 7.27PCh. 7 - Prob. 7.28PCh. 7 - Prob. 7.29PCh. 7 - Prob. 7.30PCh. 7 - Prob. 7.31PCh. 7 - Prob. 7.32PCh. 7 - Prob. 7.33PCh. 7 - Prob. 7.34PCh. 7 - Prob. 7.35PCh. 7 - Prob. 7.36PCh. 7 - Prob. 7.37PCh. 7 - Prob. 7.38PCh. 7 - P7.39 A hydrofoil 50 cm long and 4 m wide moves...Ch. 7 - Prob. 7.40PCh. 7 - Prob. 7.41PCh. 7 - Prob. 7.42PCh. 7 - Prob. 7.43PCh. 7 - Prob. 7.44PCh. 7 - P7.45 A thin sheet of fiberboard weighs 90 N and...Ch. 7 - Prob. 7.46PCh. 7 - Prob. 7.47PCh. 7 - Prob. 7.48PCh. 7 - Based strictly on your understanding of flat-plate...Ch. 7 - Prob. 7.50PCh. 7 - Prob. 7.51PCh. 7 - Prob. 7.52PCh. 7 - Prob. 7.53PCh. 7 - *P7.54 If a missile takes off vertically from sea...Ch. 7 - Prob. 7.55PCh. 7 - Prob. 7.56PCh. 7 - Prob. 7.57PCh. 7 - Prob. 7.58PCh. 7 - Prob. 7.59PCh. 7 - Prob. 7.60PCh. 7 - Prob. 7.61PCh. 7 - A sea-level smokestack is 52 m high and has a...Ch. 7 - For those who think electric cars are sissy, Keio...Ch. 7 - Prob. 7.64PCh. 7 - Prob. 7.65PCh. 7 - Prob. 7.66PCh. 7 - The Toyota Prius has a drag coefficient of 0.25, a...Ch. 7 - Prob. 7.68PCh. 7 - Prob. 7.69PCh. 7 - P7.70 The Army’s new ATPS personnel parachute is...Ch. 7 - Prob. 7.71PCh. 7 - Prob. 7.72PCh. 7 - Prob. 7.73PCh. 7 - Prob. 7.74PCh. 7 - Prob. 7.75PCh. 7 - P7.76 The movie The World’s Fastest Indian tells...Ch. 7 - Prob. 7.77PCh. 7 - Prob. 7.78PCh. 7 - Prob. 7.79PCh. 7 - Prob. 7.80PCh. 7 - Prob. 7.81PCh. 7 - Prob. 7.82PCh. 7 - Prob. 7.83PCh. 7 - P7.84 A Ping-Pong ball weighs 2.6 g and has a...Ch. 7 - Prob. 7.85PCh. 7 - Prob. 7.86PCh. 7 - P7.87 A tractor-trailer truck has a drag area CA =...Ch. 7 - P7.88 A pickup truck has a clean drag area CDA of...Ch. 7 - Prob. 7.89PCh. 7 - Prob. 7.90PCh. 7 - Prob. 7.91PCh. 7 - Prob. 7.92PCh. 7 - A hot-film probe is mounted on a cone-and-rod...Ch. 7 - Baseball drag data from the University of Texas...Ch. 7 - Prob. 7.95PCh. 7 - Prob. 7.96PCh. 7 - Prob. 7.97PCh. 7 - A buoyant ball of specific gravity SG 1 dropped...Ch. 7 - Prob. 7.99PCh. 7 - Prob. 7.100PCh. 7 - Prob. 7.101PCh. 7 - Prob. 7.102PCh. 7 - Prob. 7.103PCh. 7 - Prob. 7.104PCh. 7 - Prob. 7.105PCh. 7 - Prob. 7.106PCh. 7 - Prob. 7.107PCh. 7 - Prob. 7.108PCh. 7 - Prob. 7.109PCh. 7 - Prob. 7.110PCh. 7 - Prob. 7.111PCh. 7 - Prob. 7.112PCh. 7 - Prob. 7.113PCh. 7 - Prob. 7.114PCh. 7 - Prob. 7.115PCh. 7 - Prob. 7.116PCh. 7 - Prob. 7.117PCh. 7 - Suppose that the airplane of Prob. P7.116 is...Ch. 7 - Prob. 7.119PCh. 7 - Prob. 7.120PCh. 7 - Prob. 7.121PCh. 7 - Prob. 7.122PCh. 7 - Prob. 7.123PCh. 7 - Prob. 7.124PCh. 7 - Prob. 7.125PCh. 7 - Prob. 7.126PCh. 7 - Prob. 7.127PCh. 7 - Prob. 7.1WPCh. 7 - Prob. 7.2WPCh. 7 - Prob. 7.3WPCh. 7 - Prob. 7.4WPCh. 7 - Prob. 7.5WPCh. 7 - Prob. 7.6WPCh. 7 - Prob. 7.7WPCh. 7 - Prob. 7.8WPCh. 7 - Prob. 7.9WPCh. 7 - How does the concept of drafting, in automobile...Ch. 7 - Prob. 7.11WPCh. 7 - Prob. 7.12WPCh. 7 - Prob. 7.1FEEPCh. 7 - Prob. 7.2FEEPCh. 7 - Prob. 7.3FEEPCh. 7 - Prob. 7.4FEEPCh. 7 - Prob. 7.5FEEPCh. 7 - Prob. 7.6FEEPCh. 7 - Prob. 7.7FEEPCh. 7 - Prob. 7.8FEEPCh. 7 - Prob. 7.9FEEPCh. 7 - Prob. 7.10FEEPCh. 7 - Prob. 7.1CPCh. 7 - Prob. 7.2CPCh. 7 - Prob. 7.3CPCh. 7 - Prob. 7.4CPCh. 7 - Prob. 7.5CPCh. 7 - It is desired to design a cup anemometer for wind...
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