A motor runs at 20 V. The resistance of the armature is 11 ohm. If the back emf produced is 198 V, when at full speed, then calculate the current through armature, when (i) motor is just switched on and (ii) motor is at full speed.

A motor runs at 20 V. The resistance of the armature is 11 ohm. If the

1.	A motor runs at 20 V. The resistance of the armature is 11 ohm. If the back emf produced is 198 V, when at full speed, then calculate the current through armature, when (i) motor is just switched on and (ii) motor is at full speed.
Answer» Here, `V = 220 V, R = 11 Omega, E = 198 V` Current at full speed `I = (V - E)/(R )` `= (220 - 198)/(11) = (22)/(11) = 2 A` When motor is just switched on, `E = 0` `:. I = (V)/(R ) = (220)/(11) = 20 A`

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A motor runs at 20 V. The resistance of the armature is 11 ohm. If the back emf produced is 198 V, when at full speed, then calculate the current through armature, when (i) motor is just switched on and (ii) motor is at full speed.

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