Transformer Objectives 1.Describe how a transformer works by watching a video clip. 2.Apply the transformer equations by solving problems.

What do you do if you have an electrical appliance that requires 220 V but the electrical outlet provides only 110 V?

What is a transformer? A device that transfers electrical energy from one circuit to another by electromagnetic induction (also called transformer action). Most often used to step up or step down voltage. Electrical energy is always transferred without a change in frequency A varying current in the primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic flux through the secondary winding. This varying magnetic flux induces a varying electromotive force (EMF), or "voltage", in the secondary winding.

Transformers

The primary and the secondary coils

Basic Transformer Action

secondary voltage is greater than the primary voltage. receives a low voltage and converts it into a higher voltage.

secondary voltage is smaller than the primary voltage. receives a high voltage and converts it into a lower voltage.

Transformer equations

Ohm’s law and Power equations