Explore topic-wise MCQs in Dc Machines.

This section includes 6 Mcqs, each offering curated multiple-choice questions to sharpen your Dc Machines knowledge and support exam preparation. Choose a topic below to get started.

1.

By changing the polarity of the armature of failed self-exciting machine, machine can be started.

A. True
B. False
Answer» B. False
Discussion
2.

Which of the following is not a reason, behind failing of self-exciting machine?

A. Residual magnetism is absent
B. Negative feedback
C. Field resistance value is more than critical resistance value
D. Armature resistance is non-zero
Answer» E.
Discussion
3.

DC generator will not self-excite in __________

A. Positive feedback
B. Negative feedback
C. Zero Feedback
D. Doesn t depend on feedback
Answer» C. Zero Feedback
Discussion
4.

No-load voltage observed at two different field resistance values, is V1 < V2. What will be the relation in speed if field resistance is kept same for both cases?

A. N<sub>1</sub> &lt; N<sub>2</sub>
B. N<sub>1</sub> = N<sub>1</sub>
C. N<sub>1</sub> &gt; N<sub>1</sub>
D. Can t determine from no-load voltage
Answer» B. N<sub>1</sub> = N<sub>1</sub>
Discussion
5.

No-load voltage observed at two different field resistance values, is V1 &lt; V2. What will be the relation in field resistance values?

A. Rf<sub>1</sub> &lt; Rf<sub>2</sub>
B. Rf<sub>1</sub> = Rf<sub>1</sub>
C. Rf<sub>1</sub> &gt; Rf<sub>1</sub>
D. Can t determine from no-load voltage
Answer» D. Can t determine from no-load voltage
Discussion
6.

No-load voltage can t be defined where _____________

A. Field resistance line lies below the magnetization linear line
B. Field resistance line intersects the magnetization linear line
C. Field resistance line coincides the magnetization linear line
D. Defined everywhere
Answer» D. Defined everywhere
Discussion