Answer / sreekanth

In a DC supply constant voltage is maintained.. whereas in AC voltage and current are changed..we know the basic principal of transformer is mutual inductance..for which current in one coil must change uniformly.. in DC supply it is not possible so DC supply is not used for transformers..

Answer / dinesh vishwakarma

bcoz it work on the principle of electromagnetic induction and
it is not happens in dc

Answer / navya.suryadevera

Transformer works on the mutual induction principle.when dc
supply is given to the transformer there is no alternating
flux in secondary.Constant emf will be induced causes
winding of the transformer get over heated and finally damaged.

Answer / nandhini

transformer works on mutual inductance through alternating flux produced by AC.assume that if we give DC to a transformer ,there is a static flow of current(no flux produced) which produces more amount of heat ,so the coil melts,there is no inductance between the coil.

Answer / navya

If dc supply can be used for transformer then no emf will be used in the transformer.Due to this reason if dc supply is given to transformer then transformer windings will burn out.

Answer / kumar

Bcoz if u given dc supply 2 transformer input, current
increases infintly large & due to magnetostiction effect
the winding of transformer burns out

Answer / prashant

the transformer winding burns when DC is applied

Answer / manikandan

Dc supply can be fed to the transformer ..but it should be
fed slowly however there ll not be any change in the o/p
since there is no path for flux the windings ll not
burn..but in competitive exam if these type of q uestion
asked means answer the winding ll burn...

Answer / vicky

The simple answer s induction principle s only applicable for ac...

Answer / kavitha

transformer is a static device.emf is induced only when
there is a rotating part.if we are giving dc supply flux
produced by dc supply also remains constant.hence there is
no emf will be induced in secondary.so when we giving ac
supply time vary flux will be produced.for this reason we
are giving only dc supply.

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