A $\text{250 V}$ dc shunt motor has an armature resistance of $0.2\:\Omega$ and a field resistance

of $100\:\Omega$. When the motor is operated on no-load at rated voltage, it draws an

armature current of $\text{5 A}$ and runs at $\text{1200 rpm}$. When a load is coupled to the

motor, it draws total line current of $\text{50 A}$ at rated voltage, with a $5$ % reduction in

the air-gap flux due to armature reaction. Voltage drop across the brushes can be

taken as $\text{1 V}$ per brush under all operating conditions. The speed of the motor, in

$\text{rpm}$ under this loaded condition, is closest to:

1. $1200$
2. $1000$
3. $1220$
4. $900$
in new
edited