(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An LR circuit has a resistance R = 25 Ω, an inductance L = 5.4 mH, and a battery of EMF = 9.0 V. How much energy is stored in the inductance of this circuit when a steady current is achieved?

2. Relevant equations

[itex]\epsilon[/itex]= -d[itex]\phi[/itex]_{m}/dt=-L[itex]\frac{dI}{dt}[/itex]

U_{m}=[itex]\frac{1}{2}[/itex]LI^{2}

L=[itex]\phi[/itex]_{m}/I

3. The attempt at a solution

According to the equations, to find the energy stored in the inductance of the circuit, I need to find current, but I don't know how. For the equation of emf, by a "steady" current, I suppose this means that dI/dt is equal to zero. I don't know how that helps, but it's as far as I got trying to understand this problem. Perhaps there is an equation that is necessary to solve this problem, but nothing comes to mind. Maybe... Ohm's law? But I doubt it as the potential difference across the circuit isn't known, and I don't think emf can be substituted for potential difference V even thought they have the same units (voltage).

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# Homework Help: Energy stored in an inductor of an LR circuit

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