Questions 14

Questions

1.Instrument transformers normally:

a.convert 14 volts DC to 26 volts AC

b.reduce the AC supply to 26 volts for some instruments

c.change 115 volts to 200 volts for engine instruments

d.convert 28 volts DC to 28 volts AC

2.An autotransformer:

a.varies its turns ratio automatically to maintain a constant output voltage with varying input voltage

b.has only one coil which is used as both primary and secondary

c.will maintain a constant output frequency with a varying supply frequency

d.requires an inductive supply

3.A step up transformer is one in which the number of turns on the secondary winding is:

a.the same as the primary if the cable diameter is the same

b.greater than that on the primary

c.less than on the primary

d.always the same as on the primary

4.A transformer which halves the voltage will have:

a.twice as many turns on the secondary as on the primary

b.half as many turns on the secondary as on the primary

c.half as much current flowing in the secondary as in the primary

d.four times as many turns on the secondary as on the primary

5.The power output of a transformer is:

a.in proportion to the transformation ratio

b.in inverse proportion to the transformation ratio

c.the same as the power input

d.increased in a step up transformer

6.With no load across the output terminals of a transformer:

a.the current flow will be maximum

b.the current flow will be negligible

c.the current will be in phase with the voltage

d.the voltage in the primary will be always greater than the secondary

7.If the voltage induced in the secondary windings is greater than that in the primary then the transformer is:

a.an autotransformer

b.a step up

c.a step down

d.a magnetic amplifier

Questions 14

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14 Answers

Answers

1	2	3	4	5	6	7
b	b	b	b	c	b	b

Answers 14

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