Answer / chandrasekhar chatterjee

after giving dc supply to ac transformer,magnetic saturation occurs after a while.As a result flux will remain constant i.e.there will be no change of flux.And as a result no emf will b generated.
2.In dc supply frequency is 0.so all the inductances in transformer act as a short ckt.So huge current will flow and will damage the coil.

Answer / tarun aggarwal ymca

If DC supply is fed to a transformer's primary, then inductive reactance X1 and magnetising reactance X0 becomes zero. The no load branch contain a parallel combination of R0 and X0. As X0 is zero so that the impedance of no load branch is zero. and current being the ratio of Supply Voltage and no load impedance is very high as it burn the primary winding.

Answer / sri devi

if the dc supply is given the transformer will not work.
because transformer acts on mutual induction principle. so
the alternating current required to run the transformer.

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