Font size
WorksheetsSINGLE PHASE TRANSFORMER
Total questions: 15
Worksheet time: 8mins
The size of a transformer core will depend on
(a) frequency
(b) frequency and area of the core
(c) flux density of the core material.
A shell-type transformer has
(a) high eddy current losses
(b) reduced magnetic leakage
(c) negligibly hysteresis losses
(d) none of the above
If ∅m is the maximum value of flux in the core then the average rate of change of flux is
a. f∅m
b. 2 f∅m
c. 4 f∅m
d. 4.44 f∅m
If the supply frequency of a transformer increases, the secondary output voltage of the transformer
Increase
Decrease
Remain the same
NONE OF THE ABOVE
Lamination of the transformer core is made of
Cast Iron
Silicon Steel
Aluminum
Cast Steel
A transformer transform
Current
Voltage & current
Frequency
Voltage
A Step-Up Transformer which has 110/220 turns.What would happen if we replace it with 10/20 turns? (because Turns ratio would be same in both cases)
induced E.M.F wold be same
Induced E.M.F would be decreased
Induced E.M.F would be increased
None of the above
The rating of transformer may be expressed in ____________.
kW
KVA
KVAR
HORSE POWER
What will happen if the primary of a transformer is connected to D.C supply?
Transformer will operate with low efficiency
Transformer will operate with high efficiency
No effect
Transformer may start to smoke and burn
A Step Up transformer _____________.
Step Up the level of Voltage
Step down the level of current
Step up level the power
Step up the level of Frequency
1 and 2 only
In Single Phase Transformer, The Primary Current and Primary Voltage is 4.55 and 11kV respectively. The Rating of the transformer would be________?
50kVA
86kVA
100kVA
150kVA
An Isolation Transformer Has Primary to Secondary turns ratio of __________.
1 : 2
2 : 1
1 : 1
Can be any ratio
A Transformer______________.
Changes ac to DC
Changes dc to AC
Steps up or down DC Voltages & Current
Steps up or down AC Voltages & Current
Kindly mark the right answers
Transformer is --------
Transfer Electrical power from one electrical circuit to another Electrical circuit It’s working without changing the frequency
Work through on electro magnetic induction.
When, both circuits take effect of mutual induction Can step up or step down the level of voltage.
Its Working without changing the Power.
DC power is never applied to transformer
True
False
