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+//Problem 21.19: A 100 V d.c. generator supplies a current of 15 A when running at 1500 rev/min. If the torque on the shaft driving the generator is 12 Nm, determine (a) the efficiency of the generator and (b) the power loss in the generator.

+

+//initializing the variables:

+T = 12; // in Nm

+I = 15; // in Amperes

+V = 100; // in Volts

+n = 1500/60; // in rev/sec

+

+//calculation:

+//the efficiency of a generator = (output power/input power)*100 %

+//The output power is the electrical output, i.e. VI watts. The input power to a generator is the mechanical power in the shaft driving the generator, i.e. T*w or T(2*pi*n) watts, where T is the torque in Nm and n is speed of rotation in rev/s. Hence, for a generator 

+//efficiency = V*I*100/(T*2*pi*n)  %

+eff = V*I*100/(T*2*%pi*n) // in  Percent

+//The input power = output power + losses

+// hence, T*2*%pi*n = V*I + losses

+Pl = T*2*%pi*n - V*I

+

+printf("\n\n Result \n\n")

+printf("\n (a) efficiency is %.2f percent ",eff)

+printf("\n (b) power loss is %.0f W ",Pl)
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