A 205 V shunt motor is rated at 5 HP and 1000 rpm. At rated output it draws 29 A of line current. The total armature circuit resistance is 0.5 2. The field resistance is 101 Q. Find the armature current.

A 240 V d.c. series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 ohm. The value of resistance which must be added to obtain rated torque at 1000 rpm is ?

A series motor runs at 800 rev/min when the voltage is 400V and the current is 25A. The armature resistance is 0.4 ohm and the series field resistance is 0.2 ohm. Determine the resistance to be connected in series to reduce the speed to 600 rev/min with the same current.

A 120 V shunt motor has an armature equivalent of 0.5 ohm and a field resistance of 60 ohm. At full load, the motor takes 10 A and the speed is 1000 rpm. At what speed must this motor maybe driven as a generator to deliver 10 A to an external load at 120 V?

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Please question 4

A 220 V DC series motor runs drawing a current of 30 A from the supply. Armature and field circuit resistances are 0.4 and 0.1 respectively. The load torque varies as the square of the speed. The flux in the motor may be taken as being proportional to the armature current. To reduce the speed of the motor by 50% the resistance in ohms that should be added in series with the armature is

A 230 V dc series motor has an armature resistance of 0.2 ohm and field resistance of 0.1 ohm at rated voltage. The motor draws a line current of 40 amperes and runs at a speed of 1000 rpm. Find speed of the motor for line current of 20 A at 230 V. Assume that flux at 20 A line current is 60% of flux at 40 A line current.

A 250 V d.c. shunt motor takes a current of 20 A. Resistance of shunt field winding is 200 ohm and the armature is 0.3 ohm. What is the current in the armature ?

A series motor runs at 700 rev/min when the voltage is 300 V and the current is 20 A. The armature resistance is 0.3 2 and the series field resistance is 0.1 2. Determine the resistance to be connected in series to reduce the speed to 500 rev/min with the same current