At $$50\% $$ of full load, the armature current drawn by a $$d.c.$$ shunt motor is $$40$$ A when connected to a $$200$$ $$V$$ $$d.c.$$ mains. By decreasing the field flux, its speed is raised by $$20\% $$ this also causes a $$10\% $$ increase in load torque. Calculate the percentage change in field current. The armature resistance including the brushes is $$1$$ $$Ohm.$$ Neglect saturation and armature reaction.

GATE 1997 Electrical Engineering PYQ — Electrical Machines

GATE 19971997PYQNATanswer pendingexplanation soonhard

Electrical Machines · DC Machines

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DC Machines has appeared in GATE Electrical Engineering 64 times across 30 years (2021, 2022, 2023, 2024, 2025, ...).