## Answer #91

The answer is (d): both bulbs will go off slowly, with the same
timing, as seen in an mpeg video by clicking your mouse on the photograph
at the left below.

At the instant when the switch is removed from the circuit, the circuit
consists of the inductor with two light bulbs in series. The magnetic
field in the transformer will then collapse, inducing current in its
windings that decreases with the characteristic time constant T = L/R,
where R is the series resistance of the inductor and the two light bulbs
and L is the inductance.

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