Answer / swapnil

no dc transformer does not exist . If a transformer is
given dc supply no emf would be induced in the secondary of
transfomer as there is no flux linkage between primary &
secondary the primary would draw more current from the
supply mains and the primary would be burnt .

Answer / pheba

A transformer is not a device to convert variable dc to
const dc.... it is used to step up, step down or to
transmit a particular level of voltage....
dc can be amplified using amplifier.... can be reduced
using pot dividers....so dc transformer doesn't make any
sense...

Answer / glenn gross

a transformer conveys energy by a change of magnetic flux. The change is essential. No change- no induction in the secondary. As such it is an AC only device and because of it magnetic core properties it is only efficient at frequencies it is designed for- like 50-50 hertz, or 400 hz or 1 mhz. Step out of the efficient frequency band and its useless

Answer / ajay bharija

no there is no dc transformer because if we use DC there is
always a positve cycle .so at the time of switch ON,from 0
to + ve,we will get little o/p voltage.Since the resistance
of primary winding is quite low therefore a heavy current
will flow through primary winding ,which may burn out the
primary winding.

Answer / poornima

There is no dc transformer because, we know the equation i.e,

R=1/(2*3.14*f) ; for dc supply the frequency is 0 Hz which means r is at infinity.. If R is infinity means then very small amount of current i.e at negligible amount....Hence transformer will not work.....so only there is no dc transformer.

Answer / tarkeshwar

yes DC transformer exist....we can say Chopper is a DC
transformer which convert ariable dc voltage into constant
dc voltage.

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