LR Circuits: an LR Circuit Contains an Ideal 60-V Battery

question 37

Multiple Choice

LR circuits: An LR circuit contains an ideal 60-V battery, a 51-H inductor having no resistance, a 21-Ω resistor, and a switch S, all in series. Initially, the switch is open and has been open for a very long time. At time t = 0 s, the switch is suddenly closed. When the voltage across the resistor is equal to the voltage across the inductor, what is the current in the circuit?

• A) 1.4 A
• B) 0.57 A
• C) 1.1 A
• D) 0.86 A
• E) 1.7 A

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Definitions:

Serous Cells

Gland cells that produce a watery, protein-rich fluid, playing key roles in lubrication and protection in various organs and cavities of the body.

Mucus Neck Cells

Specialized cells in the stomach that produce mucus to protect the lining of the stomach from acidic gastric juice.

Adventitia

The outermost layer of the wall of a blood vessel or other organ, consisting mainly of connective tissue, providing structural support and protection.

Serosa

The outermost layer of tissue that envelops some internal organs, part of the lining of the body cavities and a structure involved in protection and secretion.