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motion through it against the voltage induced by the growing
magnetic field. The energy was in fact stored in the magnetic field, in
a similar way to the storage of mechanical energy when force is
applied to set a heavy vehicle in motion.
Just as the vehicle gives up its stored energy when it is brought to a
standstill, the result being the heating of the brakes, so the magnetic
field in L gave up its energy when the current was brought to a
standstill, the result being the heating of R. Self-inductance is
therefore analogous to mechanical inertia.
The amount of energy stored when a current / is flowing is again
equal to the charge Q transferre ...