$A$ transformer connected to a $220 \, V$ line shows an output of $2 \, A$ at $11000 \, V$. The efficiency is $100 \%$. The current drawn from the line is ...... $A$.

In a lossless transformer,an alternating current of $2 \ A$ is flowing in the primary coil. The number of turns in the primary and secondary coils are $100$ and $20$ respectively. The value of the current in the secondary coil is.......$A$

An $AC$ source of internal resistance $10^3 \Omega$ is connected to a transformer. The ratio of the number of turns in the primary to the number of turns in the secondary to match the source to a load resistance of $10 \Omega$ is

For the given circuit,comment on the type of transformer used:

$A$ small town with a demand of $800 \; kW$ of electric power at $220 \; V$ is situated $15 \; km$ away from an electric plant generating power at $440 \; V$. The resistance of the two-wire line carrying power is $0.5 \; \Omega/km$. The town gets power from the line through a $40,000-220 \; V$ step-down transformer at a sub-station in the town.
$(a)$ Estimate the line power loss in the form of heat.
$(b)$ How much power must the plant supply,assuming there is negligible power loss due to leakage?
$(c)$ Characterise the step-up transformer at the plant.
(Neglect,as before,leakage losses). Hence,explain why high-voltage transmission is preferred?

Why is a soft iron core used in a transformer?