---
title: "An ideal battery, a resistor of resistance \\(R\\), an air-core inductor, and an open switch are connected in series. A ferromagnetic core with permeability \\(\\mu > \\mu_0\\) is inserted into the interior of the inductor. How do the self-inductance of the coil and the time constant for current growth in the circuit after the switch is closed compare to their original values before the core was inserted?"
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url: "https://nerd-notes.com/ubq/118632/"
date_modified: "2026-08-04T08:13:18+00:00"
---

# An ideal battery, a resistor of resistance \(R\), an air-core inductor, and an open switch are connected in series. A ferromagnetic core with permeability \(\mu > \mu_0\) is inserted into the interior of the inductor. How do the self-inductance of the coil and the time constant for current growth in the circuit after the switch is closed compare to their original values before the core was inserted?

An ideal battery, a resistor of resistance \(R\), an air-core inductor, and an open switch are connected in series. A ferromagnetic core with permeability \(\mu > \mu_0\) is inserted into the interior of the inductor. How do the self-inductance of the coil and the time constant for current growth in the circuit after the switch is closed compare to their original values before the core was inserted?

- **A.** Self-Inductance: Decreases | Time Constant: Decreases
- **B.** Self-Inductance: Increases | Time Constant: Increases
- **C.** Self-Inductance: Increases | Time Constant: Decreases
- **D.** Self-Inductance: Decreases | Time Constant: Increases

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/118632/*