An independently excited DC electric motor running at a speed of 5000 vg/min without load is supplied with a 115 V power source as shown in Figure 2. The motor runs at a speed of 1500 vg/min at a torque of 0.7 Nm. Ignore losses and the supply voltage remains unchanged compared to the rating. Let's calculate a. Armature resistance of the motor; b. The voltage applied to the armature means the motor produces a torque of 5 Nm and a speed of 1400 vg/min.

 

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