Core-Type Transformers

What does 'Double wound' mean in the context of transformers?

• A transformer designed for dual voltage inputs

• A transformer that can double the input voltage

• A transformer with more than one winding

• A transformer with two iron cores

What is the purpose of using a laminated core in a transformer?

• To increase the magnetic field

• To improve the transformer's appearance

• To reduce eddy currents and power losses

• To make the transformer lighter

What is the effect of applying an AC voltage to the primary winding of a transformer?

• It causes a changing magnetic flux to circulate in the iron core

• It directly increases the output voltage

• It decreases the magnetic flux in the core

• It creates a static magnetic field

What is back EMF?

• The voltage that stabilizes the transformer

• The voltage induced in the secondary circuit

• The voltage that opposes the applied voltage in the primary circuit

• The voltage used to power the transformer

Why are transformer windings made from insulated, low resistance conductors?

• To increase the transformer's weight

• To prevent short circuits within windings or to the core itself

• To make the transformer more expensive

• To decrease the transformer's efficiency

What does the 'Turns ratio' of a transformer describe?

• The ratio of the transformer's weight to its power output

• The ratio of primary to secondary turns affecting the induced emf

• The difference in voltage between the primary and secondary windings

• The difference between the amount of windings on the primary and secondary sides

What principle allows a transformer to induce a current in the secondary coil?

• Direct current induction

• Capacitive coupling

• Resistive transfer

• Mutual inductance

What is the main reason for the high efficiency of transformers?

• The use of high resistance materials

• The absence of moving parts

• The application of direct current

• The use of non-ferrous core materials

How do eddy currents affect a transformer's efficiency?

• They improve the magnetic coupling between coils

• They have no effect on the transformer's efficiency

• They increase the transformer's efficiency

• They generate resistive losses, reducing efficiency

What is the relationship between power input and output in an ideal transformer?

• There is no relationship between power input and output

• POWER INPUT = POWER OUTPUT assuming 100% efficiency

• POWER INPUT > POWER OUTPUT as it generates extra power

• POWER INPUT < POWER OUTPUT due to losses