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 22, Problem 17RQ
Name two problems a refrigeration system may have if the condensing unit is exposed to a low-ambient condition when not equipped with a low-ambient head pressure control valve.
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If the rods are made from a square section with the dimension as shown. Calculate the load
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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
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(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
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(a) p=d sin
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T
where T Number of teeth on the sprocket.
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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.…
Chapter 22 Solutions
Refrigeration and Air Conditioning Technology (MindTap Course List)
Ch. 22 - Why do some condensers have to be cleaned with...Ch. 22 - The three materials of which condensers are...Ch. 22 - Who should be consulted when condenser cleaning is...Ch. 22 - When is the most heat removed from the refrigerant...Ch. 22 - After heat is absorbed into a condenser medium in...Ch. 22 - A water-cooling tower capacity is governed by what...Ch. 22 - When a standard-efficiency air-cooled condenser is...Ch. 22 - Four methods for controlling head pressure in an...Ch. 22 - The prevailing winds can affect which of the...Ch. 22 - True or False: Air-cooled condensers are much more...
Ch. 22 - The type of condenser that has the lowest...Ch. 22 - Compare the standard conditions of high-efficiency...Ch. 22 - Name two ways in which the heat from an air-cooled...Ch. 22 - Briefly describe what is meant by floating head...Ch. 22 - Explain how to flush impurities from a...Ch. 22 - Explain the basic operation of a combination ORI...Ch. 22 - Name two problems a refrigeration system may have...Ch. 22 - Briefly explain what is meant by condenser...
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- 7. A motor shaft rotating at 1440 r.p.m. has to transmit 15 kW to a low speed shaft rotating at 500 r.p.m. The teeth are 20° involute with 25 teeth on the pinion. Both the pinion and gear are made of cast iron with a maximum safe stress of 56 MPa. A safe stress of 35 MPa may be taken for the shaft on which the gear is mounted. Design and sketch the spur gear drive to suit the above conditions. The starting torque may be assumed as 1,25 times the running torque. Ruins 20 LW at 100 nm to another shaft running approxiarrow_forward6. A two stage reduction drive is to be designed to transmit 2 kW; the input speed being 960 r.p.m. and overall reduction ratio being 9. The drive consists of straight tooth spur gears only, the shafts being spaced 200 mm apart, the input and output shafts being co-axial.arrow_forward2 A metal block of mass m = 10 kg is sliding along a frictionless surface with an initial speed Vo, as indicated below. The block then slides above an electromagnetic brake that applies a force FEB to the block, opposing its motion. The magnitude of the electromagnetic force varies quadratically with the distance moved along the brake (x): 10 FEB = kx², with k = 5 N m² V₁ = 8 m/s m = 10 kg FEB Frictionless surface Electromagnetic brake ⇒x Determine how far the block slides along the electromagnetic brake before stopping, in m.arrow_forward
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