The insulating material used between the commutator segments is normally_____________?
Correct answer: C. mica
- A. graphite
- B. paper
- C. mica
- D. insulating varnish
Explanation
Mica is used between commutator segments because it has high dielectric strength, good mechanical stability, and withstands the heat and wear of commutation. Graphite and varnish do not provide the required segment insulation.
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