SSE JE Electrical Engineering 10 Dec 2020 Papers

Induced emf of the transformer can be determined as
${\mathrm{E}}_1=4.44\mathrm{\varphi }\mathrm{f}{\mathrm{N}}_1$
${\mathrm{E}}_2=4.44\mathrm{\varphi }\mathrm{f}{\mathrm{N}}_2$
Where,
${\mathrm{E}}_1=$ RMS value of primary side induced emf
${\mathrm{E}}_2=$ RMS value of secondary side induced emf
$\mathrm{\varphi }=$ flux
${\mathrm{N}}_1=$ Number of turns in the primary side
${\mathrm{N}}_2=$ Number of turns in the secondary side
$\mathrm{f}=$ supply frequency
∴ RMS value of the inducted EMF/turn in a transformer is given by
$\frac{{\mathrm{E}}_1}{{\mathrm{N}}_1}=\frac{{\mathrm{E}}_2}{{\mathrm{N}}_2}=4.44\mathrm{f}{\mathrm{\varphi }}_{\mathit{m}}$
This is called the emf equation of transformer, which shows, emf/number of turns is the same for both primary and secondary winding.