1 files changed, 15 insertions, 0 deletions
diff --git a/3760/CH4/EX4.56/Ex4_56.sce b/3760/CH4/EX4.56/Ex4_56.sce
new file mode 100644
index 000000000..14a2cccb7
--- /dev/null
+++ b/3760/CH4/EX4.56/Ex4_56.sce
@@ -0,0 +1,15 @@
+clc;
+v=230; // rated voltage of dc series motor
+n=1500; // speed at rated output
+i=20; // current drawn at rated output
+ra=0.3; // armature resistance
+rf=0.2; // field resistance
+disp('case a');
+// At starting Ea=0, therefore 
+re=(v/i)-(ra+rf);
+printf('External resistance to be added in motor armature circuit to develop rated torque is %f ohms\n',re);
+disp('case b');
+n2=1000; // speed at rated torque has to be developed
+Ea2=(n2/n)*(v-i*(ra+rf)); // counter EMF at n=1000 rpm
+re=(v-Ea2-i*(ra+rf))/i;
+printf('External resistance to be added in motor armature circuit to develop rated torque is %f ohms\n',re);