The Transformer
Transformer is a device, which is used to increase or decrease the alternating voltage. The transformers are of the following types
(i) Step-up transformer (ii) Step-down transformer
Transformer is based upon the principle of mutual induction. It consists of two coils, primary coil `(p)` and secondary coil `(s)`, insulated from each other wounded on soft iron core.
Often the primary coil is the input coil and secondary coil is the output coil. These soft iron cores are laminated to minimise eddy current loss.
The ratio of secondary to primary turns in an ideal transformer is 4 : 5. If power input is P, then the ratio of power output to power input is
Options:
(a) 4 : 9
(b) 9 :4
(c) 5 : 4
(d) 1:1