For a transformer with a winding ratio of N1 ( pri ) and N2 ( secondary
), Voltage on the secondary ( E2 )
Voltage on the Primary ( E 1 )
Current on secondary ( I 2 )
Current on Primary ( I 1 )

E1/E2 = N1/N2 = I2 / I1 , E1 * C1 = E2 * I2

The first equation is the volttage steps up in the same ratio as the
windings.\
The current steps up in the inverse ratio of the windings.

The second equation is just power in equal power out ( neglecting
slight losses )

Dan