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//CHAPTER 8- DIRECT CURRENT MACHINES
//Example 30
disp("CHAPTER 8");
disp("EXAMPLE 30");
//Series DC motor 5 HP with 100 rpm
//VARIABLE INITIALIZATION
p=5*735.5; //in Watts (1 metric H.P.=735.5 W)
N=1000; //in rpm, given as 100 rpm but solved as 1000 rpm in the text book
//hence taken 1000 rpm
I=30; //in Amperes
I_s=45; //starting current in Amperes
//SOLUTION
T=(p*60)/(2*%pi*1000); // Torque
//Torque dir prop phi.Ia
//=> since phi dir prop Ia
//=> torque dir prop Ia^2
// starting torque T_s / T = Starting current Ia ^2 / I^2
T_s=(T*(I_s^2))/(I^2);
disp(sprintf("The starting torque is %.0f N-m",T_s));
//The answer is slightly different due to precision of floating point numbers
//END
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