7. A coil having a resistance of 20 ohms and an inductance of 0.75 henry is connected in series with a 30-ohm resistor and to a 120-volt d-c source. A switch across the series resistor is then closed, and the circuit is assumed to be in a steady-state condition. At the instant the switch is opened, what will be the rate of current change and the power delivered by the magnetic field.

7. A coil having a resistance of 20 ohms and an inductance of 0.75 henry is connected in series with a 30-ohm resistor and to a 120-volt d-c source. A switch across the series resistor is then closed, and the circuit is assumed to be in a steady-state condition. At the instant the switch is opened, what will be the rate of current change and the power delivered by the magnetic field.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 8RQ

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