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For a DC motor taking 10kW power from 230V mains, having armature resistance and field resistance equal to 0.08Ω and 115Ω resp. The value of armature current is_____

For a DC motor taking 10kW power from 230V mains, having armature resistance and field resistance equal to 0.08Ω and 115Ω resp. The value of armature current is_____ Correct Answer 41.48 A

Field current is equal to 230/115 = 2A, by Ohm’s law. When running as a motor line current IL= 10k/230= 43.48A. Since power is taken from 230V mains, Ia=IL- If = 43.48-2 =41.48A. For generating mode Ia= IL+ If.

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