$A$ step-down transformer transforms $220 \text{ V}$ to $11 \text{ V}$. If the currents in the primary and secondary coils are $5 \text{ A}$ and $90 \text{ A}$ respectively,the efficiency of the transformer is: (in $\%$)

$A$ transformer operating at primary voltage $8\,kV$ and secondary voltage $160\,V$ serves a load of $80\,kW$. Assuming the transformer to be ideal with a purely resistive load and working on unity power factor,the resistances in the primary and secondary circuits would be:

$A$ transformer with efficiency $80\%$ works at $4\, kW$ and $100\, V$. If the secondary voltage is $200\, V$, then the primary and secondary currents are respectively:

$A$ transformer has $120$ turns in the primary coil and carries $5 \text{ A}$ current. Input power is $1 \text{ kW}$. To have $560 \text{ V}$ output, the number of turns in the secondary coil will be:

How does a transformer affect the voltage and current?

Primary side of a transformer is connected to $230 \ V, 50 \ Hz$ supply. The turns ratio of primary to secondary winding is $10:1$. The load resistance connected to the secondary side is $46 \ \Omega$. The power consumed in it is: (in $W$)