
Electric Motors and Control Systems
2nd Edition
ISBN: 9780073373812
Author: Frank D. Petruzella
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 4.4, Problem 1RQ
Define the term actuator as it applies to an electric circuit.
Expert Solution & Answer

Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Please find the torsional yield strength, the yield strength, the spring index, and the mean diameter. Use: E = 28.6 Mpsi, G = 11.5 Mpsi, A = 140 kpsi·in, m = 0.190, and relative cost= 1.
A viscoelastic column is made of a material with a creep compliance of
D(t)= 0.75+0.5log10t+0.18(log10t)^2 GPA^-1
for t in s. If a constant compressive stress of σ0 = –100 MPa is applied at t = 0, how long will it take (= t1/2) for the height of the column to decrease to ½ its original value? Note: You will obtain multiple answers for this problem! One makes sense physically and one does not.
A group of 23 power transistors, dissipating 2 W each, are to be cooled by attaching them to a black-anodized square aluminum plate and mounting the plate on the wall of a room at 30°C. The emissivity of the transistor and the plate surfaces is 0.9. Assuming the heat transfer from the back side of the plate to be negligible and the temperature of the surrounding surfaces to be the same as the air temperature of the room, determine the length of the square plate if the average surface temperature of the plate is not to exceed 50°C. Start the iteration process with an initial guess of the size of the plate as 43 cm.
The properties of air at 1 atm and the film temperature of (Ts + T)/2 = (50 + 30)/2 = 40°C are k = 0.02662 W/m·°C, ν = 1.702 × 10–5 m2 /s, Pr = 0.7255, and β = 0.003195 K–1.
Multiple Choice
0.473 m
0.284 m
0.513 m
0.671 m
Chapter 4 Solutions
Electric Motors and Control Systems
Ch. 4.1 - Prob. 1RQCh. 4.1 - Prob. 2RQCh. 4.1 - What do the terms normally open and normally...Ch. 4.1 - The types of enclosures used to house motor...Ch. 4.1 - Prob. 5RQCh. 4.1 - Compare the operation of momentary and maintained...Ch. 4.1 - What is the OSHA requirement for resetting...Ch. 4.1 - Prob. 8RQCh. 4.1 - Explain how a push-to-test pilot light operates.Ch. 4.1 - Compare the way in which pushbutton and selector...
Ch. 4.1 - Prob. 11RQCh. 4.2 - Define the term mechanically operated switch.Ch. 4.2 - In what way are limit switches normally actuated?Ch. 4.2 - A control application calls for an NC held open...Ch. 4.2 - List four common types of limit switch operator...Ch. 4.2 - Prob. 5RQCh. 4.2 - Prob. 6RQCh. 4.2 - For what types of machine control applications are...Ch. 4.2 - How does a fluid capillary tube temperature switch...Ch. 4.2 - Prob. 9RQCh. 4.2 - Prob. 10RQCh. 4.3 - In general, how do sensor pilot devices operate?Ch. 4.3 - What is the main feature of a proximity sensor?Ch. 4.3 - List the main component of an inductive proximity...Ch. 4.3 - Explain the term hysteresis as it applies to a...Ch. 4.3 - How is a two-wire sensor connected relative to the...Ch. 4.3 - In what way is the sensing field of a capacitive...Ch. 4.3 - For what type of target would a capacitive...Ch. 4.3 - Prob. 8RQCh. 4.3 - Name the three most common scan techniques for...Ch. 4.3 - What are the advantages of fiber optic sensing...Ch. 4.3 - Outline the principle of operation of a Hall...Ch. 4.3 - Outline the principle of operation of an...Ch. 4.3 - List the four basic types of temperature sensors...Ch. 4.3 - Compare the way in which a tachometer and magnetic...Ch. 4.3 - Outline the principle of operation of an optical...Ch. 4.3 - What approach is usually taken to measurement of...Ch. 4.3 - Prob. 17RQCh. 4.4 - Define the term actuator as it applies to an...Ch. 4.4 - In what ways are electromagnetic relays employed...Ch. 4.4 - Prob. 3RQCh. 4.4 - Prob. 4RQCh. 4.4 - Prob. 5RQCh. 4.4 - Prob. 6RQCh. 4.4 - Prob. 7RQCh. 4.4 - Prob. 8RQCh. 4.4 - Prob. 9RQCh. 4.4 - What is the basic difference between an open-loop...Ch. 4.4 - Prob. 11RQCh. 4.4 - Prob. 12RQCh. 4.4 - In what way docs a double-break contact differ...Ch. 4.4 - Prob. 14RQCh. 4.4 - Prob. 1TCh. 4.4 - Prob. 2TCh. 4.4 - Prob. 4TCh. 4.4 - Prob. 5TCh. 4.4 - A through-beam photoelectric sensor appears to be...Ch. 4.4 - Prob. 1DTCh. 4.4 - Prob. 2DTCh. 4.4 - Prob. 3DTCh. 4.4 - What does the range adjustment on a float switch...Ch. 4.4 - A stepper motor cannot be bench-checked directly...
Additional Engineering Textbook Solutions
Find more solutions based on key concepts
CONCEPT QUESTIONS
15.CQ3 The ball rolls without slipping on the fixed surface as shown. What is the direction ...
Vector Mechanics for Engineers: Statics and Dynamics
How is the hydrodynamic entry length defined for flow in a pipe? Is the entry length longer in laminar or turbu...
Fluid Mechanics: Fundamentals and Applications
The solid steel shaft AC has a diameter of 25 mm and is supported by smooth bearings at D and E. It is coupled ...
Mechanics of Materials (10th Edition)
How does a computers main memory differ from its auxiliary memory?
Java: An Introduction to Problem Solving and Programming (8th Edition)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- A 40-cm-diameter, 127-cm-high cylindrical hot water tank is located in the bathroom of a house maintained at 20°C. The surface temperature of the tank is measured to be 44°C and its emissivity is 0.4. Taking the surrounding surface temperature to be also 20°C, determine the rate of heat loss from all surfaces of the tank by natural convection and radiation. The properties of air at 32°C are k=0.02603 W/m-K, v=1.627 x 10-5 m²/s, Pr = 0.7276, and ẞ = 0.003279 K-1 The rate of heat loss from all surfaces of the tank by natural convection is The rate of heat loss from all surfaces of the tank by radiation is W. W.arrow_forwardA 2.5-m-long thin vertical plate is subjected to uniform heat flux on one side, while the other side is exposed to cool air at 5°C. The plate surface has an emissivity of 0.73, and its midpoint temperature is 55°C. Determine the heat flux subjected on the plate surface. Uniform heat flux -Plate, € = 0.73 Cool air 5°C 7 TSUIT Given: The properties of water at Tf,c= 30°C. k=0.02588 W/m.K, v=1.608 x 10-5 m²/s Pr = 0.7282 The heat flux subjected on the plate surface is W/m²arrow_forwardHot water is flowing at an average velocity of 5.82 ft/s through a cast iron pipe (k=30 Btu/h-ft-°F) whose inner and outer diameters are 1.0 in and 1.2 in, respectively. The pipe passes through a 50-ft-long section of a basement whose temperature is 60°F. The emissivity of the outer surface of the pipe is 0.5, and the walls of the basement are also at about 60°F. If the inlet temperature of the water is 150°F and the heat transfer coefficient on the inner surface of the pipe is 30 Btu/h-ft².°F, determine the temperature drop of water as it passes through the basement. Evaluate air properties at a film temperature of 105°C and 1 atm pressure. The properties of air at 1 atm and the film temperature of (Ts+ T∞)/2 = (150+60)/2 = 105°F are k=0.01541 Btu/h-ft-°F. v=0.1838 × 10-3 ft2/s, Pr = 0.7253, and ẞ = 0.00177R-1arrow_forward
- hand-written solutions only, please. correct answers upvoted!arrow_forwardhand-written solutions only, please. correct answers upvoted!arrow_forward! Required information Consider a flat-plate solar collector placed horizontally on the flat roof of a house. The collector is 1.3 m wide and 2.8 m long, and the average temperature of the exposed surface of the collector is 42°C. The properties of air at 1 atm and the film temperature are k=0.02551 W/m-°C, v = 1.562 × 10-5 m²/s, Pr = 0.7286, and ẞ= 0.003356 K-1 Determine the rate of heat loss from the collector by natural convection during a calm day when the ambient air temperature is 8°C. The rate of heat loss from the collector by natural convection is W.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Refrigeration and Air Conditioning Technology (Mi...Mechanical EngineeringISBN:9781305578296Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill JohnsonPublisher:Cengage LearningUnderstanding Motor ControlsMechanical EngineeringISBN:9781337798686Author:Stephen L. HermanPublisher:Delmar Cengage LearningElectrical Transformers and Rotating MachinesMechanical EngineeringISBN:9781305494817Author:Stephen L. HermanPublisher:Cengage Learning
- Automotive Technology: A Systems Approach (MindTa...Mechanical EngineeringISBN:9781133612315Author:Jack Erjavec, Rob ThompsonPublisher:Cengage Learning

Refrigeration and Air Conditioning Technology (Mi...
Mechanical Engineering
ISBN:9781305578296
Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher:Cengage Learning

Understanding Motor Controls
Mechanical Engineering
ISBN:9781337798686
Author:Stephen L. Herman
Publisher:Delmar Cengage Learning

Electrical Transformers and Rotating Machines
Mechanical Engineering
ISBN:9781305494817
Author:Stephen L. Herman
Publisher:Cengage Learning

Automotive Technology: A Systems Approach (MindTa...
Mechanical Engineering
ISBN:9781133612315
Author:Jack Erjavec, Rob Thompson
Publisher:Cengage Learning
Fluid Mechanics - Viscosity and Shear Strain Rate in 9 Minutes!; Author: Less Boring Lectures;https://www.youtube.com/watch?v=_0aaRDAdPTY;License: Standard youtube license