The ratio of secondary to primary turns in a transformer is $3 : 2$. If the power output is $P$,then the input power,neglecting all losses,must be equal to:

The instrument which works on the principle of mutual inductance is

The ratio of secondary to primary turns is $9:4$. If power input is $P$, what will be the ratio of power output (neglect all losses) to power input?

$A$ step-down transformer is connected to a main supply of $200\,V$ to operate a $6\,V$,$30\,W$ bulb. The current in the primary coil is.....$A$

What is the transformation ratio of a transformer?

The number of turns in the primary coil of a transformer is $1000$ and in the secondary coil is $3000$. If $80 \ V$ a.c. is applied to the primary,the potential difference per turn of the secondary coil is: (in $V$)