$A$ 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

$A$ transformer having an efficiency of $90 \%$ is working on a $200 \ V$ and $3 \ kW$ power supply. If the current in the secondary coil is $6 \ A$,the voltage across the secondary coil and the current in the primary coil respectively are:

$A$ 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......$A$.

In a transformer,the mutual inductance between the primary and secondary coils is $0.5 \ H$. The resistances of the primary and secondary coils are $20 \ \Omega$ and $5 \ \Omega$ respectively. To induce a current of $0.4 \ A$ in the secondary coil,what is the required rate of change of current in the primary coil in $A/s$?

The primary and the secondary coils of a transformer contain $10$ and $100$ turns, respectively. The primary coil is connected to a battery that supplies a constant voltage of $1.5 \, V$. The voltage across the secondary coil is .................. $V$.

$A$ transformer is used to step up an alternating e.m.f. of $220 \ V$ to $4.4 \ kV$ to transmit $6.6 \ kW$ of power. The primary coil has $1000$ turns. The current rating of the secondary coil is (Transformer is ideal): (in $A$)