Refrigeration and Air Conditioning Technology (MindTap Course List)
8th Edition
ISBN: 9781305578296
Author: John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher: Cengage Learning
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Textbook Question
Chapter 26, Problem 24RQ
What special valve is used in a refrigerated air drier?
A. Four-way valve
B. Defrost valve
C. Three-way valve
D. Hot gas bypass valve
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Students have asked these similar questions
3.
9.
10.
The centrifugal tension in belts
(a) increases power transmitted
(b) decreases power transmitted
(c) have no effect on the power transmitted
(d) increases power transmitted upto a certain speed and then decreases
When the belt is stationary, it is subjected to some tension, known as initial tension. The value of this
tension is equal to the
(a) tension in the tight side of the belt
(b) tension in the slack side of the belt
(c) sum of the tensions in the tight side and slack side of the belt
(d) average tension of the tight side and slack side of the belt
The relation between the pitch of the chain (p) and pitch circle diameter of the sprocket (d) is given by
60°
(a) p=d sin
(c) p=d sin
(120°
T
where T Number of teeth on the sprocket.
90°
(b) p=d sin
T
180°
(d) p=d sin
T
OBJECTIVE TYPE QUESTIONS
1.
The maximum fluctuation of energy is the
2.
(a) sum of maximum and minimum energies
(b) difference between the maximum and minimum energies
(c) ratio of the maximum energy and minimum energy
(d) ratio of the mean resisting torque to the work done per cycle
In a turning moment diagram, the variations of energy above and below the mean resisting torque line
is called
(a) fluctuation of energy
(b) maximum fluctuation of energy
(c) coefficient of fluctuation of energy
(d) none of the above
Chapter 16: Turning Moment Diagrams and Flywheel 611
The ratio of the maximum fluctuation of speed to the mean speed is called
3.
(a) fluctuation of speed
(c) coefficient of fluctuation of speed
4.
(b) maximum fluctuation of speed
(a) none of these
The ratio of the maximum fluctuation of energy to the.......... is called coefficient of fluctuation of
energy.
(a) minimum fluctuation of energy
(b) work done per cycle
The maximum fluctuation of energy in a flywheel is equal to
5.…
OBJECTIVE TYPE QUESTIONS
1.
The velocity ratio of two pulleys connected by an open belt or crossed belt is
2.
(a) directly proportional to their diameters
(b) inversely proportional to their diameters
(c) directly proportional to the square of their diameters
(d) inversely proportional to the square of their diameters
Two pulleys of diameters d, and d, and at distance x apart are connected by means of an open belt
drive. The length of the belt is
(a)(d+d₁)+2x+
(d₁+d₂)²
4x
(b)(d₁-d₂)+2x+
(d₁-d₂)²
4x
(c)(d₁+d₂)+ +2x+
(d₁-d₂)²
4x
(d)(d-d₂)+2x+
(d₁ +d₂)²
4x
3.
In a cone pulley, if the sum of radii of the pulleys on the driving and driven shafts is constant, then
(a) open belt drive is recommended
(b) cross belt drive is recommended
(c) both open belt drive and cross belt drive are recommended
(d) the drive is recommended depending upon the torque transmitted
Due to slip of the belt, the velocity ratio of the belt drive
4.
(a) decreases
5.
(b) increases
(c) does not change
When two pulleys…
Chapter 26 Solutions
Refrigeration and Air Conditioning Technology (MindTap Course List)
Ch. 26 - The two broad categories of display cases are...Ch. 26 - How are conditions maintained in open display...Ch. 26 - What are mullion heaters?Ch. 26 - The three temperature ranges for refrigeration...Ch. 26 - The two methods for rejecting heat from...Ch. 26 - When the compressors are located in the equipment...Ch. 26 - When one large compressor is used, what desirable...Ch. 26 - Define a parallel compressor system and list five...Ch. 26 - Three disadvantages of parallel compressor systems...Ch. 26 - What is the difference between an even and an...
Ch. 26 - Exactly matching the refrigeration load with the...Ch. 26 - What is the function of the pressure transducer in...Ch. 26 - What is the function of the microprocessor-based...Ch. 26 - Explain how the oil separator, oil reservoir,...Ch. 26 - Large or small compressors on parallel compressor...Ch. 26 - A(n)_______varies the frequency of an...Ch. 26 - Prob. 17RQCh. 26 - Prob. 18RQCh. 26 - Three advantages of unitary, stand-alone...Ch. 26 - How is defrost accomplished when the equipment...Ch. 26 - True or False: The two types of defrosts used with...Ch. 26 - What special precautions should be taken with...Ch. 26 - Prob. 23RQCh. 26 - What special valve is used in a refrigerated air...Ch. 26 - Briefly explain what is meant by a surge-type...Ch. 26 - Briefly explain what is meant by a subcritical...Ch. 26 - Briefly explain what is meant by a transcritical...Ch. 26 - Prob. 28RQCh. 26 - Prob. 29RQCh. 26 - Prob. 30RQCh. 26 - Prob. 31RQCh. 26 - Prob. 32RQCh. 26 - Prob. 33RQ
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