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WorksheetsTRANSFORMERS
Total questions: 10
Worksheet time: 5mins
Laminated insulation are normally used in the transformer:
To reduce the hysteresis effect
To increase the hysteresis effect
To reduce the effect of eddy current
To increase the effect of eddy current
A transformer has:
primary and secondary windings, both of which are considered inputs
a primary winding used as an output and a secondary winding used as an input
primary and secondary windings, both of which are considered outputs
a primary winding used as an input and a secondary winding used as an output
A Transformer______________
Changes dc to AC
Steps up or down AC Voltages & Current
Changes ac to DC
Steps up or down DC Voltages & Current
Increasing the number of turns of wire on the secondary of a transformer will:
decrease the secondary current
increase the primary current
increase the secondary current
have no effect on the secondary current
If the primary power of an ideal transformer having a 2:1 voltage ratio is 100 W, the secondary power is:
200 W
75 W
50 W
100 W
If dc voltage is applied to the primary of a transformer it may:
Work
Burn the winding
Give lower voltage on the secondary side
Give higher voltage on the secondary side
The primary and secondary induced emfs in two winding transformer are always:
Antiphase with each other
In phase with each other
Equal in magnitude
Determined by load on transformer secondary
A transformer does not change the following:
Frequency
Voltage
Current
None of these
Transformer ratings are usually expressed in terms of :
Voltage
KVA
kWh
KW
The noise in transformer core due to the vibrations of laminations is called:
Flicker noise
Transit time noise
Agitation noise
Humming noise
