BEE Chapter 9

What is the Working Principle of a Transformer?

• Electro magnetic induction

• Electrical Energy

• Mechanical Energy

• None

The following are the essential requirements of a transformer.

• Good Magnetic core

• Two Windings-Primary and Secondary

• Time varying Magnetic flux

• All the above

What is transformer core made up of ?

• Copper

• Iron

• Silicon Steel

• None

Winding of transformer are made up of

• Copper wire

• Iron wire

• Silicon steel

• None

The Transformation ratio of a transformer K =

• N1*N2

• N1+N2

• N1/N2

• N2/N1

The Transformer rated normally in _______

• Kwh

• V

• KVA

• None

If E2

• Step up transformer

• Step down transformer

• Equal ratio transformer

• None

If E2>E1 (ie V2>V1) then it is a

• Step up transfomer

• Step down Transfomer

• Equal ratio transformer

• None of these

If E2=E1 (ie V2=V1) then it is a

• Step up transfomer

• Step down Transfomer

• Equal ratio transformer

• None of these

The induced EMF of a transformer is proportional to ____

• Number of winding

• number of turns

• All the above

• none