$A$ transformer is employed to

$A$ step-up transformer operates on a $230 \ V$ line and a load current of $2 \ A$. The ratio of primary and secondary windings is $1:25$. Then the current in the primary is (in $A$)

$A$ step-down transformer has $50$ turns on the secondary and $1000$ turns on the primary winding. If the transformer is connected to a $220 \ V, 1 \ A$ $A$.$C$. source,what is the output current of the transformer?

$A$ power transmission line feeds input power at $2300 \ V$ to a step-down transformer with its primary winding having $4000$ turns. What should be the number of turns in the secondary in order to get output power at $230 \ V$?

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

Large transformers,when used for some time,become hot and are cooled by circulating oil. The heating of a transformer is due to: