EE-2 25 TO 50

The types of induced EMF is _______ and _______________

• statically and stationary

• mutally and stationary

• statically and mutually

• none of these

The Conductor remains stationary and flux linked with it, is changed__________

• mutually induced EMF

• self induced EMF

• both A and B

• none

In an ideal transformer 

• windings have no resistance

• core has no losses

• core has permeability

• all of the above

A transformer transforms

• frequency

• Voltage

• current

• voitage and current

Transformer works on the principle of

• Flemings left hand rule

• Flemings Right hand rule

• mutual induction

• none

Transformer is a static piece which transforms electric power from one circuit to another without changing

• Frequency

• voltage

• current

• all of the above

The EMF equation of transformer is

• 4.44fØN

• 4.44fN

• 4.44f

• 4.44Ef

an transformer having 1000 primary turns is connected to a 250 v ac supply . For a secondary 400 v,the number of secondary turns should be

• 1600

• 250

• 400

• 1250

Transformers are rated in KVA instead of KW because 

• load power factor is often not known

• kVA is fixed wherwas kW depends on load p.f.

• total transformer loss depends on volt-ampere 

• it has become customary

Transformer cores are laminated in order to 

• simplify its construction

• minimize eddy current loss

• reduce cost

• reduce hysteresis loss