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 .................. $V$.

$A$ step-down transformer has a $N_{S}$ to $N_{P}$ ratio of $1: 20$. If $8 \, V$ are developed across a $0.4 \, \Omega$ secondary load, the primary current will be: (in $ \, A$)

The self-inductance of two coils of a transformer is $20 mH$ and $30 mH$. What is the resistance between them?

An ideal transformer with a purely resistive load operates at $12\,kV$ on the primary side. It supplies electrical energy to a number of nearby houses at $120\,V$. The average rate of energy consumption in the houses served by the transformer is $60\,kW$. The value of the resistive load $(R_s)$ required in the secondary circuit will be $.........\,m\Omega$.

The coils of a step-down transformer have $500$ and $5000$ turns. In the primary coil, an $AC$ current of $4 \,A$ at $2200 \,V$ is sent. The value of the current and potential difference in the secondary coil is:

The quantity that remains unchanged in the output with respect to the input in an ideal transformer is . . . . . . .