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Diffstat (limited to '3871/CH7/EX7.4/Ex7_4.sce')
| -rw-r--r-- | 3871/CH7/EX7.4/Ex7_4.sce | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/3871/CH7/EX7.4/Ex7_4.sce b/3871/CH7/EX7.4/Ex7_4.sce new file mode 100644 index 000000000..beb6261cf --- /dev/null +++ b/3871/CH7/EX7.4/Ex7_4.sce @@ -0,0 +1,42 @@ +//===========================================================================
+//chapter 7 example 4
+
+clc;clear all;
+
+//variable declaration
+w = 23; //wattmeter reading in watts
+Rp = 2000; //resistance in Ω
+f = 100; //frequency in Hz
+L = 10*10^-3 //inductance
+V = 240; //voltage in V
+I = 4.5; //current in A
+
+//calculations
+Xp = 2*%pi*f*L; //reactance in Ω
+theta = atan(Xp/Rp);
+theta1 =(theta*180)/(%pi)
+//cos(phi)=P/V*I
+//phi = acos(P/V*I)
+//w = Pt*(cos(theta))*(cos(phi-theta))/cos(phi); //wattmeter reading
+W1 = V*I; //V*I in watts
+//phi = acos(P/W) = acos(P/1080)
+//W = P*cos(theta)*(cos(phi-theta))/cos(phi)
+//W =23 =P*cos(0.18)*cos((acos(P/1080))-0.18)/(P/V*I)
+//let cos(acos(P/1080)-0.18) =A
+//B = cos(0.18)
+//W=23 = (P*B*A)/(P/(V*I))
+// W= B*A*V*I
+//A = W/(B*V*I)
+B = cos((theta1*%pi)/180);
+A = w/(B*V*I);
+//cos(acos(P/1080)-0.18) =A
+//C =acos(P/1080) = acos(A)+0.18
+A1 =(acos(A))*(180/%pi);
+C = A1+0.18
+D = cos(C*%pi/180)
+P =1080*D;
+e = ((w-P)/P)*100; //percentage error in %
+
+//result
+mprintf("percentage error in %3.2f percentage ",e);
+
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