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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...
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What is Mutual Flux and Leakage Flux ? / Disadvantages of Leakage Flux in Transformer

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 Mutual Flux and Leakage Flux

Mutual flux and Leakage flux in a transformer


Electrical energy in a transformer is first converted to magnetic energy in the core and then converted back to electrical energy in the secondary coil. The flux that is produced by the primary MMF actually carries the energy to the secondary side. 
For proper operation of the transformer, it is thus necessary that the flux should find an easy path through the core so that it can link both the two coils. The magnetic core of a transformer including the limb and yoke, thus, must be made from good quality ferromagnetic material with low reluctance. 
Such magnetic flux, which links both primary and secondary coils while passing entirely through the core, is termed as the useful flux or the mutual flux as shown in figure. 

Apart from the useful flux, there are so called leakage fluxes, those complete their path through air or other nearby metal parts, thereby not linking primary and secondary coils simultaneously, and thus not taking part in energy transfer.


Disadvantages of Leakage Flux in Transformer

Some of the disadvantages of leakage flux in transformer are listed below:-
  1. Since leakage flux does not link primary and secondary windings simultaneously, they do not take part in energy transfer. As a result, the transformer capacity becomes less than expected.
  2. In addition to the magnetizing current drawn by the useful, the leakage flux will also drawn additional magnetizing current from the input source. Thus the total magnetizing current in the transformer is increased. 
  3. As the magnetizing current gets increased due to leakage flux, the transformer power factor gets reduced.
  4. Higher magnetizing current will also increase the total input current of the transformer.
  5. Higher input current will result in higher copper losses (I^2. R) in the transformer winding resistance.
  6. Higher copper losses will in turn reduce the efficiency and cause more heating and increase temperature rise of the transformer.
  7. In addition, higher current and poor power factor will cause increased amount of internal voltage drop in the transformer winding impedance causing poor regulation.
  8. The leakage flux may link with outer metallic parts also, such as tank, bolts, joints, and cause stray magnetic losses. These will reduce the transformer efficiency further.
  9. Increased amount of magnetizing current may cause saturation of the magnetic core. Saturation causes increase in Hysteresis and Eddy current losses and produces harmonics.
It is thus necessary to reduce the amount of flux leakage as much as possible.



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