Understanding Magnetism: Permanent, Ferro, Para, and Diamagnetic Materials
Understanding Magnetism
Permanent Magnet: Once magnetized, remains magnetized.
Ferromagnet: Easily magnetized (iron, nickel, cobalt, some rare-earth metals, magnetite).
Paramagnet: Magnetized with more difficulty.
Diamagnet: Repels magnetic fields (slightly) – “not magnetic”.
Materials are broken into smaller chunks called “domains”. Each domain has a miniature magnetic field.
Domain Differences
Even if materials look the same, at a smaller level their domains could be different – hence why some
Read MoreThermodynamics: Entropy, Coefficients, and Ideal Gases
Thermodynamics
Entropy
In a Carnot cycle, the integral of Q1/T1 from 0 to Q2/T2 equals 0, where T1 and T2 are the temperatures. This gives us Q1/T1 + Q2/T2 = 0. Considering ΔQ = at, we have at1/T1 + at2/T2 = 0, thus ∑ ΔQ/T = 0.
Now, for a cyclic transformation, ∑ ΔQ/T = ∫1a2 ΔQ/T + ∫2b1 ΔQ/T = 0. If we consider other ways of reasoning, ∫1N2 ΔQ/T, the ratio of heat transfer at different temperatures is a constant. This magnitude is called Entropy.
The third principle of thermodynamics
Read MoreUnderstanding Faraday’s and Ampere’s Laws in Electromagnetism
Faraday’s Law of Electromagnetic Induction
Faraday’s Law expresses the induced electromotive force (EMF) as a function of the variation of magnetic flux (ΦB):
EMF = – ΔΦB / Δt
The electromotive force induced in a coil is equal to the rate of change of the magnetic flux through the surface bounded by the loop. For a coil with N turns, the EMF induced is:
EMF = -N * (ΔΦB / Δt)
If the coil has tightly wound turns, the flux through each turn will be the same, and the EMF induced in the coil is the
Read MoreAcoustic Physics: Sound Wave Properties and Phenomena
Acoustic Physics: Sound Wave Properties
Elongation: The distance between the point of balance and the position of particles at a given time.
Amplitude: The distance between the highest point and the point of equilibrium, similar to elongation. (Higher energy results in greater amplitude)
Period: The time it takes a particle to complete one vibration.
Frequency: The number of times an event is repeated within a given time. Specifically, the number of vibrations performed in 1 second.
Wavelength: The distance
Read MoreChronicles of a Cataclysm: Magic, Mayhem, and Moon Mishaps
The Beginning and the Book
The world began.
A middle-aged man sat in his living room with a book. This book appeared to be an electronic book titled “Magic,” which he’d found in the attic of the home he’d just purchased. He, in his infinite wisdom, believed that the “book of magic” was just a nice-looking gimmick and that as a relic, it looked nice as a conversation starter on his coffee table. Had he treated it as such, that’s all it ever would have been.
One night, after drinking a little too much,
Read MoreUnderstanding Magnetic Fields: Definitions and Applications
Magnetic Field: Definitions and Applications
Magnetism, just as electricity, is a property that all materials possess to a greater or lesser extent. This property consists of performing actions from a distance, such as attracting and repelling, plus producing induced electric currents.
Despite the force between two electric charges behaving the same as the force between two magnetic poles, unlike electricity, an individual magnetic pole cannot be separated: poles are always found in pairs.
For example,
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