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SOLUTIONS MANUAL
For
FUNDAMENTALS OF
CHEMICAL
ENGINEERING
THERMODYNAMICS,
SI EDITION
FIRST EDITION
Kevin D. Dahm and Donald P. Visco, Jr.Random Questions Solutions Included, Rest of the Questions Answers included in the text book chapter end. 1 / 4
1 © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.
Chapter 1: Introduction
1-13. The value g = 9.81 m/s 2 is specific to the force of gravity on the surface of the
earth. The universal formula for the force of gravitational attraction is:
Where m1 and m2 are the masses of the two objects, r is the distance between the centers of the two objects, and G is the universal gravitation constant, G = 6.674 × 10 -11 N(m/kg) 2 .
- Research the diameters and masses of the Earth and Jupiter.
- Demonstrate that F = m(9.81 m/s
- is a valid relationship on the surface of
- Determine the force of gravity acting on a 1000 kg satellite that is 2000
- One of the authors of this book has a mass of 200 lbm. If he was on the
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the earth.
miles above the surface of the Earth.
surface of Jupiter, what gravitational force in lbf would be acting on him?
Solution:
- Measurements obtained from different sources will vary slightly.
DEarth ~ 12,742 km D Jupiter ~ 142,000 km MassEarth = 5.97 × 10 24 kg MassJupiter = 1.90 × 10 27 kg
- MassEarth = 5.97 × 10
24 kg RadiusEarth = 6.371 × 10 6 meters
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C. Using the universal gravitational attraction formula:
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- RadiusJupiter= 71000000 m MassJupiter= 1.898 × 10
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27 kg
Chapter 1: Introduction
2 © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.
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1-14. A gas at T = 300 K and P = 100 kPa is contained in a rigid, rectangular vessel that is 2 meters long, 1 meter wide and 1 meter deep. How much force does the gas exert on the walls of the container?
Solution:
First, 1 bar = 100,000 Pa.From physics, pressure is force per area. Therefore, force is pressure multiplied by
area:
From geometry:
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1-15. A car weighs 1360 kg, and is travelling 96 km/h when it has to make an emergency stop. The car comes to a stop 5 seconds after the brakes are applied.
- Assuming the rate of deceleration is constant, what force is required?
- Assuming the rate of deceleration is constant, how much distance is
covered before the car comes to a stop?
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Chapter 1: Introduction
3 © 2015 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.
Solution:
A. First we convert to SI units:
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B. Applying the equations of linear motion from physics:
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1-16. Solar panels are installed on a rectangular flat roof. The roof is 4 meters by 9 meters, and the mass of the panels and framing is 408 kg.
- Assuming the weight of the panels is evenly distributed over the roof, how
- The density of fallen snow varies; here assume its ~30% of the density of
much pressure does the solar panel array place on the roof?
liquid water. Estimate the total pressure on the roof if 0.1 m of snow fall on top of the solar panels.
Solution:
A. From the definitions of pressure and force:
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