What is the time constant of a series RL circuit?

A \(0.50\,\mathrm{H}\) inductor is in series with \(10\,\Omega\). Find the time constant.

What is the final current after a long time when an ideal battery \(\mathcal E\) drives a series \(R\)-\(L\) circuit?

State the current growth equation for a series RL circuit connected to a dc source.

State the current decay equation for an inductor discharging through a resistor.

A \(12\,\mathrm{V}\) source drives \(6.0\,\Omega\) and \(0.30\,\mathrm{H}\) in series. Find the final current and time constant.

For the circuit in the previous question, find the current after one time constant.

A current of \(5.0\,\mathrm{A}\) decays in an RL circuit with \(\tau=0.20\,\mathrm{s}\). Find the current after \(0.40\,\mathrm{s}\).

How long does it take a growing RL current to reach \(90\%\) of its final value?

Derive the differential equation for current growth in a series RL circuit.

Why does an inductor initially behave like an open branch when a dc source is switched on?

Why does an ideal inductor behave like a wire after a long time in a dc circuit?

Find the initial current slope for a \(12\,\mathrm{V}\) source connected to a \(0.30\,\mathrm{H}\) inductor in series with resistance.

An RL circuit has \(L=2.0\,\mathrm{H}\) and must have \(\tau=0.50\,\mathrm{s}\). Find \(R\).

A growing RL current is \(3.0\,\mathrm{A}\) after one time constant. Find its final current.

During RL current growth, what is the inductor voltage at \(t=0\) and after a long time?

An inductor with initial current \(2.0\,\mathrm{A}\) discharges through \(5.0\,\Omega\). If \(L=0.50\,\mathrm{H}\), how much energy is initially stored and where does it go?

A current decays from \(8.0\,\mathrm{A}\) to \(2.0\,\mathrm{A}\) in an RL circuit. Express the elapsed time in units of \(\tau\).

Compare the RL time constant \(L/R\) with the RC time constant \(RC\). Why does resistance appear oppositely?

Derive the RL growth solution form from the loop equation and identify the final current.