Bundle: Refrigeration And Air Conditioning Technology, 8th + Lab Manual + Lms Integrated For Mindtap Hvac-r, 4 Terms (24 Months) Printed Access Card
8th Edition
ISBN: 9781337087315
Author: John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher: Cengage Learning
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Chapter 30, Problem 8RQ
To determine
The type of the voltage signal that the voltage controller uses to power start or stop they electric heaters.
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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
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 30 Solutions
Bundle: Refrigeration And Air Conditioning Technology, 8th + Lab Manual + Lms Integrated For Mindtap Hvac-r, 4 Terms (24 Months) Printed Access Card
Ch. 30 - The material often used to manufacture electric...Ch. 30 - Portable or small space heaters with glowing coils...Ch. 30 - Baseboard heaters transfer heat by______.Ch. 30 - A disadvantage of a central forced-air electric...Ch. 30 - Three common controls used in central electric...Ch. 30 - Prob. 6RQCh. 30 - Prob. 7RQCh. 30 - Prob. 8RQCh. 30 - True or False: A package sequencer can start or...Ch. 30 - Two types of wiring diagrams are the pictorial and...
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- 5. A 15 kW and 1200 r.p.m. motor drives a compressor at 300 r.p.m. through a pair of spur gears having 20° stub teeth. The centre to centre distance between the shafts is 400 mm. The motor pinion is made of forged steel having an allowable static stress as 210 MPa, while the gear is made of cast steel having allowable static stress as 140 MPa. Assuming that the drive operates 8 to 10 hours per day under light shock conditions, find from the standpoint of strength, 1. Module; 2. Face width and 3. Number of teeth and pitch circle diameter of each gear. Check the gears thus designed from the consideration of wear. The surface endurance limit may be taken as 700 MPa. [Ans. m = 6 mm; b= 60 mm; Tp=24; T=96; Dp = 144mm; DG = 576 mm]arrow_forward4. G A micarta pinion rotating at 1200 r.p.m. is to transmit 1 kW to a cast iron gear at a speed of 192 r.p.m. Assuming a starting overload of 20% and using 20° full depth involute teeth, determine the module, number of teeth on the pinion and gear and face width. Take allowable static strength for micarta as 40 MPa and for cast iron as 53 MPa. Check the pair in wear.arrow_forwardI want to solve these choicesarrow_forward
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