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For a given DC series generator with critical resistance equal to 100 Ω, armature resistance is equal to 50 Ω, and series field resistance is equal to 20 Ω, is connected across load of 50 Ω. What will be the load voltage?

For a given DC series generator with critical resistance equal to 100 Ω, armature resistance is equal to 50 Ω, and series field resistance is equal to 20 Ω, is connected across load of 50 Ω. What will be the load voltage? Correct Answer 0 V

Here, DC series motor fails to excite as addition of armature resistance, load resistance and field resistance is greater than the critical resistance of the machine by 20 Ω. Thus, machine fails to self-excite, as a result we’ll get zero terminal voltage.

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