Transformer Practice Exam

[Vysakh9292]

What kVA rating is required for a transformer that must handle a maximum load current of 8 A with a secondary voltage of 2 kV?

A. 4 kVA
B. 0.25 kVA
C. 16 kVA
D. 8 kVA

[Vysakh9292]

The turns ratio required to match an 80 source to a 320 load is

A. 80
B. 20
C. 4
D. 2

[Vysakh9292]

When the turns ratio of a transformer is 20 and the primary ac voltage is 12 V, the secondary voltage is

[A]. 12 V
[B]. 120 V
[C]. 240 V
[D]. 2,400 V

[Vysakh9292]

If a transformer has 50 turns in the primary winding and 10 turns in the secondary winding, what is the reflective resistance if the secondary load resistance is 250 ?

A. 250
B. 25
C. 6,250
D. 62,500

[Vysakh9292]

The primary winding of a transformer has 110 V ac across it. What is the secondary voltage if the turns ratio is 8?

A. 8.8 V
B. 88 V
C. 880 V
D. 8,800 V

[Vysakh9292]

To step 110 V ac down to 20 V ac, the turns ratio must be

A. 5.5
B. 18
C. 0.18
D. 0.018

[Vysakh9292]

If 25 W of power are applied to the primary of an ideal transformer with a turns ratio of 10, the power delivered to the secondary load is

A. 25 W
B. 0 W
C. 250 W
D. 2.5 W

[Vysakh9292]

A transformer with a 110 V primary has a 15:1 turns ratio. The load resistance, RL, is 120 . What is the approximate voltage across the load?

A. 7.3 V
B. 73 V
C. 88 V
D. 880 V

[Vysakh9292]

How many primary volts must be applied to a transformer with a turns ratio of 0.1 to obtain a secondary voltage of 9 V?

A. 9 V
B. 90 V
C. 900 V
D. 0.9 V

[Vysakh9292]

In a certain loaded transformer, the secondary voltage is one-fourth the primary voltage. The secondary current is

A. one-fourth the primary current
B. four times the primary current
C. equal to the primary current
D. one-fourth the primary current and equal to the primary current