A transformer of efficiency 90% has turns ratio 10 : 1. If the voltage across the primary is 220 V and current in the primary is 0.5 A, then the current in secondary is

Options

A. `60 Omega`
B. `50 Omega`
C. `80 Omega`
D. `100 Omega`

Answer

D

Explanation

Input power = `4kW ` , Efficiency is 90%
`therefore ` output power = `0.9 xx 4 kW = 3.6 kW`
`3.6 kW = I^2 R = 36 xx R`
`R = (3.6 kW)/(36) = (3.6 xx 10^3)/36 = 10^2 omega = 100 Omega`