Transformers Current and Voltage

[xvivi]

Homework Statement

A transformer has a turns ratio of 5 : 1. It is connected to a 230 V supply and an output (secondary) current of 2.7 A is measured. If the transformer is 90% efficient, calculate:

1. Secondary voltage
2. Input (primary) current

[/B]

Homework Equations

Pout/Pin*100=efficiency[/B]

The Attempt at a Solution

I don't think it can be solved as most of the equations dealing with transformers assume an ideal transformer.[/B]

 

[Noctisdark]

Hi Xvivi,
The ratio is 5:1, just to remind that even the tronsformer isn't 100% efficient the output is yet the same, the only thing that changes is the ouput current,
You can pull out the ouput voltage, use the fact of thethe 90% efficiency to determine the input current, good luck !

 

[NascentOxygen]

I don't think it can be solved as most of the equations dealing with transformers assume an ideal transformer.

In your analysis here you do include an ideal transformer, then add an external resistance to it to account for its non-ideality.

 

[CWatters]

Work out the secondary voltage assuming an ideal transformer.
Work out the output power
Work out the input power allowing for the efficiency being 90%
Work out the input current.