#### Transcript Transformers

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**Transformers**

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**Parts of a transformer**

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**Using a transformer to change voltage**

The voltage induced in the secondary (output) coil depends on the number of turns on the primary and secondary coils. A

**step-up transformer**

has more turns on the secondary coil and so

**increases voltage**

.

3 of 6 A

**step-down transformer**

has fewer turns on the secondary coil and so

**decreases voltage**

.

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**Investigating transformers**

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**Properties of transformers**

Transformers transfer power between circuits. The design of a transformer determines the characteristics of the electricity flowing in its secondary circuit. The

**frequency**

of the alternating current in the secondary circuit matches the primary circuit, but what about voltage?

The voltage in each circuit is related to the

**number of coils**

on each side of a transformer by the following formula:

**primary voltage secondary voltage = primary turns secondary turns**

*V*

**p**

*V*

**s =**

*N*

**p**

*N*

**s**

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**Calculating voltage**

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