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RICH DAD POOR DAD BOOK REVIEW

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  RICH  DAD  POOR  DAD  BOOK REVIEW This is amazing book.   • Explodes the myth that you need to earn a high income to become rich • Challenges the belief that your house is an asset • Shows parents why they can't rely on the school system to teach their kids about money • Defines once and for all an asset and a liability • Teaches you what to teach your kids about money for their future financial success It's been nearly 25 years since Robert Kiyosaki’s  Rich Dad Poor Dad  first made waves in the Personal Finance arena. It has since become the #1 Personal Finance book of all time... translated into dozens of languages and sold around the world. Rich Dad Poor Dad  is Robert's story of growing up with two dads — his real father and the father of his best friend, his rich dad — and the ways in which both men shaped his thoughts about money and investing. The book explodes the myth that you need to earn a high income to be rich and explains the difference between working
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What is Magnetic Circuits ?

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 Magnetic Circuits

A magnetic circuits can be defined as the path which is followed by magnetic flux.
An example of magnetic circuit is given below:-





The Core is made of iron. Iron being a good magnetic material (high value of relative permeability), flux produced by the iron core will entirely pass through the iron core and thus magnetic field intensity(H) can be assumed to remain fixed at every point within the iron core.

Magnetic field intensity developed by the iron core, Hc = Ni /lc    AT/m

Flux density within the iron core, Bc = μo μr Hc   Wb/m^2
where μr is the relative permeability of iron material used in the iron core.

The amount of flux flowing through the iron core, 
Ⲫc = B.Ac
or,  Ⲫc = μo μr Hc Ac
or,  Ⲫc = μo μr (Ni /lc) Ac
or,  Ⲫc = Ni /(lc /μo μr Ac)
or,  Ⲫc = Ni /S

Product of number of turns (N) in the coil and current (i) passing it i.e. (F=Ni) is known as the Magneto Motive Force (MMF).
MMF is the source that produces magnetism in a magnetic circuit. 
MMF is analogous to EMF in an electric circuit and can be defined as the magnetic potential difference that forces magnetic flux to flow through a magnetic circuit.

S = lc /μo μr Ac  is called reluctance of the magnetic flux path that is a measure of how much opposition the flux faces while flowing through the magnetic circuit.
unit of reluctance is AT/Wb

Reluctance is inversely proportional to relative permeability, it is obvious that a good magnetic material (high value of μr) will offer less opposition (low reluctance) to the flux flowing through it.

The quantity  1/μo μr   is called Specific reluctance or reluctivity of the magnetic material.


Sometimes, energy conversion device like generators or motors may have air gap between stator & rotor, when air gap is much smaller than the dimensions of adjacent core faces, magnetic flux will follow the path defined by air gap & core.





We know that, 
Flux, Ⲫc = MMF(F=NI) / Reluctance(S)

F = Ⲫc.S

F = Ⲫc.[ Sc + Sg ]

Sc = lc / μc.Ac  ,   Sg = g / μo.Ag

Where, g = air gap length
Ag = area of cross section of air gap

So, introduction of air gap increases the reluctance in the path of flux. So, to maintain same flux machines draw more amount of magnetizing current.




Comments

  1. adextermagJune 9, 2021 at 1:55 PM

    I am attracted by the presentation of this article. This information about Magnetic, is really good. I really appreciate your work. It is a gainful article for us. Keep posting. Thank you.
    Magnetic Bead Separation

    ReplyDelete
  2. adextermagJuly 9, 2021 at 5:28 PM

    You've shared some quite useful information about Magnetic. This is a fantastic opportunity for us to expand our knowledge while also being beneficial to us. Thank you for bringing this story to our attention.
    Magnetic Actuator

    ReplyDelete

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