A commutator in a d.c. machine (A) Reduces power loss in armature. (B) Reduces power loss in field circuit. (C) Converts the induced a.c armature voltage into direct voltage. (D) Is not necessary.

A commutator in a d.c. machine
 (A) Reduces power loss in armature.
 (B) Reduces power loss in field circuit.
 (C) Converts the induced a.c armature voltage into direct voltage.
 (D) Is not necessary.
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2 Answers

Answer :

(C) Converts the induced a.c armature voltage into direct voltage.
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Answer :

Ans: C
 As name suggests, it commutes ac into dc.
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Related questions

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Three factors responsible for the change in voltage as load is applied to an AC generator are: 1) the drop in resistance in the armature circuit, 2) the change in flux, and 3) the ____________. A. armature winding speed B. inductance load drop C. coil pitch factor D. armature reactance voltage drop

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A d.c. shunt motor runs at no load speed of 1140 r.p.m. At full load, armature reaction weakens the main flux by 5% whereas the armature circuit voltage drops by 10%. The motor full load speed in r.p.m. is (A) 1080 (B) 1203 (C) 1000 (D) 1200

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Last Answer : Answer: C

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Last Answer : Answer: C

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Last Answer : Answer: C

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