Transformer and Its working

Transformers

Statement-1 : A transformer cannot work on dc supply. Statement-2 : dc changes neither in magnitude nor in direction.

Assertion : A transformer cannot work on dc supply. Reason : dc changes neither in magnitude nor in direction.

Assertion (A) : A transformer does not work on DC Reason (R) : DC neither change direction nor magnitude.

Asseration: A transformer cannot work on dc supply. Reason: there is no effect of earth's magnetic field on freely falling body.

Assertion : When a current flows in the coil of a transformer then its core becomes hot. Reason : The core of transformer is made of softiron.

(i) Draw a labelled diagram of a step-down transformer. State the principle of its working. (ii) Find the ratio of primary and secondary currents in terms of turn ratio in an ideal transformer. (iii) How much current is drawn by the primary of a transformer connected to 220V supply when it delivers power to a 110V-550W refrigerator ?

The basic requirment for the operation of a transformer is that its input voltage must be