The quantity that remains unchanged in a transformer is:

What is the transformation ratio of a transformer?

$A$ transformer has $100$ turns in the primary coil and carries $8 A$ current. If the input power is $1 \text{ kW}$,the number of turns in the secondary coil,to have $500 \text{ V}$ output,will be $:-$

$A$ step-down transformer is connected to a $2400 \, V$ line, and $80 \, A$ of current is found to flow in the output load. The ratio of the turns in the primary and secondary coil is $20 : 1$. If the transformer efficiency is $100\%$, then the current flowing in the primary coil will be: (in $A$)

$A$ transformer has $100$ turns in the primary coil and carries $8$ $A$ current. If input power is $1$ $kW$, the number of turns in the secondary coil to have $500$ $V$ output will be

$A$ step-down transformer is used to reduce the main supply from $V_1$ volt to $V_2$ volt. The primary coil draws a current $I_1$ $A$ and the secondary coil draws $I_2$ $A$. $(I_1 < I_2)$. The ratio of input power to output power is