G9 Chapter 21

A transformer consists of

• Metal Core

• Metal core and coiled wire

• Metal core and polymer wire

• Polymer core and metal wire

Transformer is device that

• converts AC voltage to current

• converts electrical energy to kinetic energy

• converts AC voltage to a different level at the same amplitude

• converts AC voltage to a different level at the same frequency

What is the material used for construction of transformer core?

• Aluminium

• Copper

• Iron

• Wood

Primary loop is connected to the supply while secondary loop is connected to the load.

• True

• False

The winding of wire around a core which is connected to a source of energy is called the ....... coil.

• primary

• secondary

• tertiary

The function of a transformer is to ...

• raise and lower the apparent power levels

• transfer DC voltage from the primary winding to the secondary winding

• increase or decrease A.C voltage or A.C current levels

• transform mechanical energy into electrical energy

Why transformers work with A.C. current but not D.C.

• A.C current produces changing magnetic field.

• D.C current produces changing magnetic field.

• D.C current is weak

• A.C current is powerful

Transformer is always connected to ___________ supply.

• A.C.

• D.C.

For increasing the voltage ___________ is used.

• Step up transformer

• Step down transformer

• Current transformer

Transformer transforms _________ from primary to secondary.

• Only Current

• Only Voltage

• Both Voltage and Current