5. A 20KW dc shunt generator delivering rated output at 1000rpm has a terminal voltage of 500 V. The armature resistance is 0.1 ohm,voltage drop per brush is 1 V and the field resistance is 500 ohms....

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Extracted text: 5. A 20KW dc shunt generator delivering rated output at 1000rpm has a terminal voltage of 500 V. The armature resistance is 0.1 ohm,voltage drop per brush is 1 V and the field resistance is 500 ohms. Calculate the speed at which this machine will run as a motor taking an input of 20 Kw from 500 V dc.