Download Electromagnetism William Gilbert (15401603) Hans Christian

Electromagnetism.notebook
May 11, 2015
Electromagnetism
Tried to find a connection William Gilbert (1540­1603)
Hans Christian Oersted (1777­1851) between electrostatic force and magnetic force due to the similarities between the two.
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Electromagnetism.notebook
May 11, 2015
Oersted's Principle: (Re: The Magnetic Field Around a Straight Conductor)
A charge moving through a straight conductor produces a circular magnetic field around the conductor. The field is represented by concentric rings. The electric current causes the magnetic field.
Right Hand Rule # 1 Grasp the straight conductor with your right hand. The thumb points in the direction of the conventional current (positive to negative). The curved fingers point in the direction of the magnetic field around the conductor.
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Electromagnetism.notebook
May 11, 2015
Magnetic Dipoles ~ at present, scientists believe that magnetic dipoles in solid ferromagnetic materials are related to Oersted's principle. A magnetic dipole is created by the spinning of electrons in individual atoms. Quantum theory states that the spin can only be clockwise or counter clockwise.
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Electromagnetism.notebook
May 11, 2015
Paramagnetic is the term used to describe material with unpaired electrons exhibiting a small magnetic field i.e. iron, nickel, cobalt
Diamagnetic is the term used to describe materials that are weakly repelled by a magnetic field. These materials have paired electrons that produce no measurable magnetic field because of opposite spin cancellation. 4
Electromagnetism.notebook
May 11, 2015
Right Hand Rule # 2 Field Lines around a Solenoid
The fingers of the right hand curve in the direction of the conventional current (positive to negative) while the thumb points in the direction of the magnetic field lines (North).
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Electromagnetism.notebook
May 11, 2015
Four Factors That Determine the Strength of an Electromagnet
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Electromagnetism.notebook
May 11, 2015
Magnetic Permeability μ
μ = magnetic field strength with core material present
magnetic field strength with coil only
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Electromagnetism.notebook
May 11, 2015
Copy Table 9.3 Magnetic Permeability from pg 445
pg 446 # 1­4
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