Physics-
General
Easy
Question
A coil of self inductance
is joined to the terminals of a battery of e.m.f. 
through a resistance of 
and a steady current is flowing through the circuit. If the battery is now disconnected, the time in which the current will decay to 1/
of its steady value is
The correct answer is:
Time in which the current will decay to
of its steady value is 
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