Transformer » Exercise – 1
1. A transformer transforms :
(a) frequency
(b) voltage
(c) current
(d) voltage and current
2. Which of the following is not a basic element of a transformer ?
(a) core
(b) primary winding
(c) secondary winding
(d) mutual flux
3. In an ideal transformer :
(a) windings have no resistance
(b) core has no losses
(c) core has infinite permeability
(d) all of the above
4. The main purpose of using core in a transformer is to :
(a) decrease iron losses
(b) prevent eddy current loss
(c) eliminate magnetic hysteresis
(d) decrease reluctance of the common magnetic circuit
5. Transformer cores are laminated in order to :
(a) simplify its construction
(b) minimise eddy current loss
(c) reduce cost
(d) reduce hysteresis loss
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