With a diagram, explain the working of a transformer.

Explanation

A transformer is a device used for varying AC voltages. It works on the principle of mutual induction. Working : As the current through the primary varies, the magnetic flux linked with the secondary also varies. As a result, alternating emf of the same frequency is induced across the secondary. The magnitude of the induced voltage in the secondary, depends on the voltage across primary. If `V_(p)` and `V_(s)` are the input and output voltages respectively and `N_(p)` and `N_(s)` are the number of turns in the primary and secondary respectively then M
`(V_(s))/(V_(p))=(N_(s))/(N_(p))=T`
power output = power input
`(v_(s))/(v_(p))=(I_(p))/(I_(s ))`

for practical transformer efficiency
`=(V_(s)I_(s))/(V_(P)I_(P))lt I`