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OmegaFury
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Homework Statement
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?
Homework Equations
[itex]\epsilon[/itex]= -d[itex]\phi[/itex]m/dt=-L[itex]\frac{dI}{dt}[/itex]
Um=[itex]\frac{1}{2}[/itex]LI2
L=[itex]\phi[/itex]m/I
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).