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Answer Posted / atul
as we know emf is indused only if there is change in flux
and it is propotional to rate of change of flux.since a.c.
is alternating so flux changes hence emf is induced.on the
other hand dc is constant so flux is constant and hence
rate of change of flux is zero so no emf induced.
emf=-d(flux)/dt.
flux=constant in d.c
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