Question { 12402 }

what happen if we give square wave instead of sine wave to
the transformer

Answer

Ya its true that frequency remains same but it will give a
pulse when magnitude of square wave changes. so output can
never be a sine wave or a square wave either.
In short when dI/dt(Chande in magnitude or direction of
current) will be there ... u will find change in output
also.

rather to say dI/dt v can say dQ/dt(change in flux) which
ultimately depends on change in current.

So in square wave flux changes after T/2 period only so at
T/2 interval output will be a pulse only.