Question

A transformer is to be used to provide power for a computer disk drive that needs 6.0 V (rms) instead of the 120 V (rms) from the wall outlet. The number of turns in the primary is 400, and it delivers 500 mA (the secondary current) at an output voltage of 6.0 V (rms). Find the number of turns in the secondary.

Answer 1

`N_(2)`=20 turns

Step-by-step explanation:

The given case is a step down transformer as we need to reduce 120 V to 6 V.

number of turns on primary coil N_{P}= 400

current delivered by secondary coil I_{S}= 500 mA

output voltage = 6 V (rms)

we know that

`I_(p)=(V_(out))/(V_(in)* I_(s))`

putting values we get

`I_(p)=(6)/(120* 0.5)`

`I_(p)= 0.1 A`

to calculate number of turns in secondary

`(N_(2))/(400) =(6)/(120)`

therefore,
`N_(2)`=20 turns