logo

CuriousTab

CuriousTab

Discussion


Home Electrical Engineering Transformers Comments

  • Question
  • A certain amplifier has 600 Ω internal resistance looking from its output. In order to provide maximum power to a 4 Ω speaker, what turns ratio must be used in the coupling transformer?


  • Options
  • A. 8
  • B. 0.8
  • C. 0.08
  • D. 80

  • Correct Answer
  • 0.08 


  • Transformers problems


    Search Results


    • 1. To step 120 V ac up to 900 V ac, the turns ratio must be

    • Options
    • A. 75
    • B. 750
    • C. 7.5
    • D. 0.13
    • Discuss
    • 2. 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 Ω?

    • Options
    • A. 250 Ω
    • B. 25 Ω
    • C. 6,250 Ω
    • D. 62,500 Ω
    • Discuss
    • 3. The primary winding of a transformer has 110 V ac across it. What is the secondary voltage if the turns ratio is 8?

    • Options
    • A. 8.8 V
    • B. 88 V
    • C. 880 V
    • D. 8,800 V
    • Discuss
    • 4. 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?

    • Options
    • A. 4 kVA
    • B. 0.25 kVA
    • C. 16 kVA
    • D. 8 kVA
    • Discuss
    • 5. When a 200 Ω load resistor is connected across the secondary winding of a transformer with a turns ratio of 4, the source "sees" a reflective load of

    • Options
    • A. 50 Ω
    • B. 12.5 Ω
    • C. 800 Ω
    • D. 0 Ω
    • Discuss
    • 6. The mutual inductance when k = 0.65, L1 = 2 µH, and L2 = 5 µH is

    • Options
    • A. 2 mH
    • B. 2 µH
    • C. 4 µH
    • D. 8 µH
    • Discuss
    • 7. The turns ratio required to match an 80 Ω source to a 320 Ω load is

    • Options
    • A. 80
    • B. 20
    • C. 4
    • D. 2
    • Discuss
    • 8. A transformer

    • Options
    • A. changes ac to dc
    • B. changes dc to ac
    • C. steps up or down dc voltages
    • D. steps up or down ac voltages
    • Discuss
    • 9. The primary winding of a power transformer should always be

    • Options
    • A. open
    • B. shorted
    • C. switched
    • D. fused
    • Discuss
    • 10. The primary coil of a transformer is connected to a 60 V ac source. The secondary coil is connected to a 330 Ω load. The turns ratio is 3:1. What is the secondary voltage?

    • Options
    • A. 2 V
    • B. 20 V
    • C. 180 V
    • D. 18 V
    • Discuss


    Comments

    There are no comments.

Enter a new Comment