i) When current flows, the change in current in the dc coil causes a flux which links with the coil in 2nd circuit
thus an e.m.f is induced When closed, no more change in flux in dc hence no induced e.m.f
ii) I. Increasing turns in primary coil using more cells in the primary coil
II. Reversing terminals of the battery.
sharon kalunda answered the question on May 30, 2019 at 08:18
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