Question

A step-down transformer is connected to `2400` volts line and `80` amperes of current is found to flow in output load. The ratio of the turns in primary and secondary coil is `20:1.` if transformer efficiency is `100%`, then the current flowing in primary coil will be
A. 1600 A
B. 20 A
C. `4A`
D. 1.5 A

Answer 1

Correct Answer - C
`(I_(P))/(I_(S))=(n_(S))/(n_(P))`
`therefore I_(P)=(n_(S))/(n_(P))xxI_(S)=(1)/(20)xx80=4A`