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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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Questions of DC Machine

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Solved Examples

 Problem: A 4 pole generator supplies a current of 143 A. It has 492 conductors lap connected and delivering full load, brushes are given a shift of lead to 10°. calculate demagnetizing ampere turns per pole? The field winding is shunt connected and takes 10 A. Find no. of extra shunt turns necessary to neutralize this demagnetization.

Solution: Current in armature, Ia = 143 + 10 = 153 A
ꞵelect = P/2 * 10° = 4/2 * 10° = 20°
Z = 492
A = P = 4,  (A=P for lap winding)

Far (demagnetizing) = {(Z/2) / P} * {(2ꞵelect) / 180°} * {Ia / A}
                             
                                 = {492 / (2*9)} * {(2*20°) / 180°} * {153 / 4}
                 
                                 = 522.75 AT/pole

Extra field turns = 522.75 / 10 = 53 turns



Problem: Neglecting all losses, the developed torque (T) of a d.c. separately excited motor, operating under constant terminal voltage, is related to its output power (P) as?

Solution: Power developed, P = Eb.Ia = 2𝜋NT / 60     

P ∝ NT     ⇒ T ∝ P / N

For a given Torque, Speed is constant.

∴ T ∝ P .



Problem: A 4 pole dynamo with wave wound armature has 51 slots containing 20 conductors in each slot. The induced emf is 357 volts and the speed is 8500 rpm. The flux per pole will be?

Solution: For wave winding, A =2
P=4, S=51
Number of conductors, Z= 51*20 =1020
N=8500 rpm
Induced emf, Ea=357 V

Ea = ⲫZNP / 60A

⇒ ⲫ = 60EaA / ZNP = (60*357*2) / (1020*8500*4) = 1.23 mWb

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