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diff --git a/1938/CH2/EX2.30/2_30.jpg b/1938/CH2/EX2.30/2_30.jpg
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diff --git a/1938/CH2/EX2.30/2_30.sce b/1938/CH2/EX2.30/2_30.sce
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+clc,clear
+printf('Example 2.30\n\n')
+
+V=220
+I_L=52
+N_1=750, N_2=600
+R_a=0.2, R_sh = 110 //armature and shunt field resistance
+
+I_sh=V/ R_sh
+I_a1= I_L - I_sh
+I_a2=I_a1//T (prop.) I_a  and T is constant
+E_b1 = V - I_a1*R_a
+
+//N (prop.) E_b/phi (prop.) E_b
+E_b2 = E_b1*(N_2/N_1)
+R_x  = (V- E_b2)/I_a2 -R_a  //Because E_b2 = V - I_a2*(R_a+R_x)
+printf('Resistance to be connected in series = %.2f ohms\n',R_x)
+
+//After R_x gets connected in series with armature and 110 ohms in series with field winding
+N_1=600
+I_sh2=V /(R_sh+110)
+I_a1=50,I_sh1=2,I_sh2=1
+//T (prop.) I_a*I_sh and T doesn't vary
+I_a2 = I_a1*(I_sh1/I_sh2)
+E_b1 = V - I_a1*(R_a+R_x)
+E_b2 = V - I_a2*(R_a+R_x)
+N_2 = N_1*(E_b2/E_b1)*(I_sh1/I_sh2) //Because N (prop.) E_b/I_sh
+printf('New speed= %.3f rpm',N_2)