TRANSFORMERS QUIZ

A transformer does not posses ______changing property.

Current

Voltage

Power

Impedance

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In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of

None of these

15 A

less than 15 A

more than 15 A

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YOUR ANSWER : ?

The primary coil of a transformer is connected to a 60 V ac source. The secondary coil is connected to a 330 load. The turns ratio is 3:1. What is the secondary voltage?

180 V

20 V

18 V

2 V

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The core type transformer is generally suitable for ______

High voltage and small output

None of the listed here

Low voltage and high output

High voltage and high output

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An ideal transformer is one which has

a common core for its primary and secondary windings

interleaved primary and secondary windings

core of stainless steel and winding of pure copper metal

no losses and magnetic leakage

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Efficiency of a power transformer is of the order of

98 per cent

25 per cent

100 per cent

50 per cent

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A transformer has full load copper loss of 400 W. The copper loss at half full load will be _____.

None of the listed here

400 W

200 W

100 W

TRUE ANSWER : ?
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Leakage flux in a transformer occurs because

Air is not a good magnetic insulator

Iron core has high permeability

Transformer is not an efficient device

Applied voltage is sinusoidal

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When load on a transformer is decreased, ______loss is decreased

Copper

Hysteresis

Eddy current

Friction

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A transformer has 200 W as iron loss at full load. The iron loss at full load. The iron loss at half full load will be

400 W

50 W

100 W

200 W

TRUE ANSWER : ?
YOUR ANSWER : ?

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