Principle of a transformer : When an alternating current flows through the primary coil, an emf is induced in the neighbouring (secondary) coil.
© Main assumptions
(i) The primary resistance and current are small.
(ii) The flux linked with the primary and secondary coils is same / there is no leakage of flux from the core.
(iii) Secondary current is small.
(d) Reason due to which energy loses may occur : -
Flux leakage/ Resistance of the coils/Eddy currents/ Hysteresis