Page 208 - Solutions Manual to accompany Electric Machinery Fundamentals

Chapter 7: DC Machinery Fundamentals

7-1. The following information is given about the simple rotating loop shown in Figure 7-6:
. T
B  04 V B  48 V
.
l  5 . 0 m R  04 
r  . 0 25 m   500 rad/s
(a) Is this machine operating as a motor or a generator? Explain.
(b) What is the current i flowing into or out of the machine? What is the power flowing into or out of
the machine?
(c) If the speed of the rotor were changed to 550 rad/s, what would happen to the current flow into or
out of the machine?
(d) If the speed of the rotor were changed to 450 rad/s, what would happen to the current flow into or
out of the machine?

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