Answer:
Current amplitude, I = 5.57 A
Step-by-step explanation:
It is given that,
Effective resistance, R = 22 ohms
Inductive reactance, L = 72 ohms
Voltage of the alternating source, V = 420 volt
The total impedance of the RL circuit is given by :


Z = 75.28 ohms
From Ohm's law,



I = 5.57 A
So, the current amplitude of the electric motor is 5.57 A. Hence, this is the required solution.