Answer / sandeep

Transformer must not be connected to a DC Source because if
the primary winding is connected to DC Supply mains, the
flux produced will not vary but remain constant in magnitude
and therefore no EMF will be induced in secondary winding
except at the moment of switching ON. Also there will be NO
Back EMF induced in the primary winding. Therefore a heavy
current will be drawn from the supply which may result in
the burning of the winding.

In Transformer, If primary winding is connected to a source
of alternating voltage, an alternating flux is set up in the
laminated core and links with the secondary winding of the
transformer in which it produces mutually induced e.m.f
according to the principle Faraday's Laws of
Electromagnetic Induction.

Answer / reji

the above ans is correct. moreover, the DC resistance of T is much less compared to its reactance. ie, impedance is huge . thus when T is connected to DC, a very high current will flow and the winding will certainly burn.

Answer / aravind s

transformer works with mutual induction principle mutual induction must want change of flux or change of conductor.and transformer have non movable parts so we use principle of change of using frequency.

and also transformer works in DC (when it is pulsetting DC)

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