Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
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Chapter 2.8, Problem 60P
An exercise room has six weight-lifting machines that have no motors and seven treadmills each equipped with a 2.5-hp (shaft output) motor. The motors operate at an average load factor of 0.7, at which their efficiency is 0.77. During peak evening hours, all 13 pieces of exercising equipment are used continuously, and there are also two people doing light exercises while waiting in line for one piece of the equipment. Assuming the average rate of heat dissipation from people in an exercise room is 600 W, determine the rate of heat gain of the exercise room from people and the equipment at peak load conditions.
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H.W 5.4
Calculate the load that will make point A move to the left by 6mm, E-228GPa. The diameters
of the rods are as shown in fig. below.
2P-
PA
50mm
B
200mm
2P
0.9m
1.3m
d₁
=
=
Two solid cylindrical road AB and
BC are welded together at B and
loaded as shown. Knowing that
30mm (for AB) and d₂
50mm (for BC), find the average
normal stress in each road and the
total deformation of road AB and
BC. E=220GPa
H.W 5.3
60kN
A
For the previous example calculate the
value of force P so that the point A will not
move, and what is the total length of road
AB at that force?
P◄
A
125kN
125kN
0.9m
125kN
125kN
0.9m
B
B
1.3m
1.3m
Class:
B
Calculate the load that will make point A move to the left by 6mm, E-228GPa
The cross sections of the rods are as shown in fig. below.
183
P-
Solution
1.418mm
200mm
80mm
3P-
18.3
A
080mm
B
200mm
3P-
0.9m
إعدادات العرض
1.3m
4.061mm
Chapter 2 Solutions
Thermodynamics: An Engineering Approach
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Ch. 2.8 - Determine the specific kinetic energy of a mass...Ch. 2.8 - Calculate the total potential energy, in Btu, of...Ch. 2.8 - Determine the specific potential energy, in kJ/kg,...Ch. 2.8 - An object whose mass is 100 kg is located 20 m...Ch. 2.8 - A water jet that leaves a nozzle at 60 m/s at a...Ch. 2.8 - Consider a river flowing toward a lake at an...Ch. 2.8 - At a certain location, wind is blowing steadily at...Ch. 2.8 - What is the caloric theory? When and why was it...Ch. 2.8 - In what forms can energy cross the boundaries of a...Ch. 2.8 - What is an adiabatic process? 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