Electrical Transformers and Rotating Machines
4th Edition
ISBN: 9781305494817
Author: Stephen L. Herman
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 1, Problem 5RQ
Define the following terms:
Flux density
Permeability
Reluctance
Saturation
Coercive force
Residual magnetism
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Question 2 Calculate the amount of DC current required for the magnetic circuit given below to generate a
flux density of 1.0 T in the airgap. The details are
Number of turns, N = 400
The core is made up of steel, the B-H characteristic has been given below
The magnetic core length, le = 500 mm
The airgap length, Ig = 2 mm
The cross-sectional area of the core, Ag = 100 mm²
Neglect leakage and fringing.
Core
Cross-sectional
i(1)
area
as
Air gap
Magnetic path
length
Figure 1
2.0
1.8
B-H Curves for Various Metals
Steel
1.6
1.4
Magnetic
Saturation
1.2
1.0
0.8
Iron
근 0.4
Air
0.2
1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Magnetic Field Strength - H (A/m)
Figure 2
Flux Density - B (T)
10 cm
1.25
100
0.05 em
30 om
6.75
0.30
625
10 cm
00
1000
Magastaing inoway (A Ts
10 cm
30 cm-
A two-legged magnetic core with an air gap is shown in Fig.1. The depth of is 5 cm, the length of the
airgap is 0.08 cm, and the number of turns on the coil is 800. The magnetization curve of the core
material is shown in Fig.2. The magnetic field density in air gap is 0.7 T.
What is the total MMFin A-Turns required to magnetize both the iron core and airgap?
Nas deasiy B(T
令all
Answer by true or false *
True
False
The
magnetic
saturation
means the
domains of
iron crystal
arranged in
multi
directions
with respect
to field.
Answer by true or false *
True
False
D.C shunt
generators
are most
suitable for
arc winding
Page 2 of 2
Chapter 1 Solutions
Electrical Transformers and Rotating Machines
Ch. 1 - Is the north magnetic pole of the earth a north...Ch. 1 - What were early natural magnets known as?
Ch. 1 - The south pole of one magnet is brought close to...Ch. 1 - How can the polarity of an electromagnet be...Ch. 1 - Define the following terms:
Flux...Ch. 1 - A force of 1 ounce is equal to how many dynes?
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 relatively soft and ductile magnetic material from room temperature to 1414 degrees F. O Austenite OFerrite Cementitearrow_forwardWhat determines the strength of the magnetic field when current flows through a conductor?arrow_forwardDC and AC Subject: Find the relative permeability of the typical ferromagnetic material whose magnetization curve is shown. H = 50, 100, 500 and 1000 A-turns/m. Answer these: H = 100, 500, and 1000 A-turns/narrow_forward
- ASAParrow_forwardDC and AC subject: 1. Consider a wire carrying a current in the presence of a magnetic field, and a given flux density of 0.25 T. If the wire is 1.0 m long and carries a 0.5 A current, what is the magnitude of the force induced in the wire? 2. The wire shown is moving in the presence of a magnetic field. With the information given in the figure, determine the magnitude and direction of the induced voltage in the wire. (see the figure below)arrow_forwardFILL IN THE MISSING WORDS (some words may be used more than once) aluminum atomic bars conductivity conductor copper electricity gold insulators made metals power lines resistance sheets silver spans supports weight wire tubes 1. The electrical structure of the material from which the 2. 3. Some 4. 5. of matter is dependent upon the is have an extremely high such as high-tension are better conductors of is the best conductor, followed by and is used where between 6. Conductors are usually found in the form of forms of or to the flow of than others. is a major consideration, with long but may be in the 33arrow_forward
- DC and AC subject: Find the relative permeability of the typical ferromagnetic material whose magnetization curve is shown. H = 50, 100, 500 and 1000 A-turns/m.arrow_forwardThermal conductivity measurement for good conductors using Searle's Methodarrow_forward2-11 A sinusoidal current has an effective value of 50 A. Calculate the peak value of current.arrow_forward
- ASAParrow_forwardQuestion B4 a) The strength of the magnetic field B at a distance r from a straight conductor car- is the permeability rying a current I is given by the expression B = of free space with the value 4n × 10-7 NA-2. Two long straight wires are lined up parallel to one another at a separation of 0.2 m. Currents of 4 A and 2 A flow through the wires, both in the same direction. Calculate the value of the magnetic field strength due to the two wires at a point P on the mid-plane between them. where 2r b) Calculate period of a small satellite which is making a circular orbit just outside a planet of density 4.0 × 10³ kg/m³. Provide the answer in SI units and in hours. Use the value of the universal gravitational constant 6.7 x 10-11 N kg-2m-2. c) A mass of 0.01 kg is suspended from a light spring of natural length 80 mm and causes the spring to extend by 10 mm. The mass is pulled down a further 5 mm and then released. Assuming g = 9.8 m/s², calculate: i) the spring constant. ii) the period of…arrow_forward4. Which correctly describes the transmissibility? * Force transmitted over excitation force Percentage of absorbed force Stress over strain How much percentage of force is transmittedarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Electrical Transformers and Rotating MachinesMechanical EngineeringISBN:9781305494817Author:Stephen L. HermanPublisher:Cengage Learning
Electrical Transformers and Rotating Machines
Mechanical Engineering
ISBN:9781305494817
Author:Stephen L. Herman
Publisher:Cengage Learning
Material Properties 101; Author: Real Engineering;https://www.youtube.com/watch?v=BHZALtqAjeM;License: Standard YouTube License, CC-BY