In a transformer,the number of turns in the primary coil and secondary coil are $5$ and $4$ respectively. If $240 \ V$ is applied to the primary coil,then the ratio of the current in the primary coil to the secondary coil is:

Write important uses of transformer.

For a transformer,the turns ratio is $3$ and its efficiency is $0.75$. The current flowing in the primary coil is $2 \,A$ and the voltage applied to it is $100 \,V$. Then the voltage and the current flowing in the secondary coil are ... respectively.

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

$A$ distribution transformer with an efficiency of $90 \%$ supplies power to a colony of $10$ homes. All the $10$ homes have an electrical oven running at the same time,each drawing $20 \ A$ current from $220 \ V$ lines. The power dissipated as heat in the transformer is: (in $kW$)

The primary and secondary coils of a transformer have $50$ and $1500$ turns respectively. If the magnetic flux $\phi = \phi_0 + 4t$,where $\phi$ is in webers,$t$ is time in seconds and $\phi_0$ is a constant,the output voltage across the secondary coil is......$V$