Class 2 Midterm part 2

1. 1The secondary winding of a step-up transformer has ________ than the primary winding.

   1. Amore turns
   2. Bmore power
   3. Clower frequency
   4. Dless turns
2. 2
   Diodes conduct current:

   1. Ain both directions.
   2. Bin one direction only.
   3. Conly when connected to a capacitor.
   4. Donly after they warm up.
3. 3The number of cycles per second a source completes is called it’s __________.

   1. Avoltage
   2. Bcurrent
   3. Cfrequency
   4. Dperiod
4. 4
   Two electrically isolated inductors can be magnetically coupled together by ______ inductance, to form a transformer.

   1. Aresistive
   2. Bisolated
   3. Ccapacitive
   4. Dmutual
5. 5Capacitance is measured in ___________.

   1. AHenrys
   2. BFlux
   3. CFarads
   4. DOhms
6. 6
   Three 60µH inductors are connected in parallel. The equivalent inductance is:

   1. A60µH
   2. B20µH
   3. C180µH
   4. D3,600µH
7. 7“Normally Closed” contacts are connected to _________ when the coil of the relay is energized.

   1. Athe common
   2. B. the coil
   3. Cnothing
   4. Dthe “Normally Open” contacts
8. 8An AC (sinusoidal) source drives a 100Ω load to 141.4 Volts Peak. The average power delivered is:

   1. A10W
   2. B100W
   3. C1000W
   4. Dzero
9. 9
   A transformer is a device that may used to ____________.

   1. Astep up or down voltages and currents.
   2. Btransfer energy by mutual inductance.
   3. Cisolate one part of a circuit from another.
   4. Dall of the above.
10. 10An open primary in a transformer results in:

    1. Adecreased DC resistance in the secondary.
    2. Bincreased DC resistance in the secondary.
    3. Can overcurrent condition.
    4. Dno induced voltage in the secondary.

11. 11Primary current causes a magnetic field in the _______ of a transformer.

    1. Acore
    2. Bcapacitance
    3. Clabel
    4. Dwires
12. 12
    A capacitor opposes a change in ________ across it.

    1. Avoltage
    2. Bcurrent
    3. Cresistance
    4. Dfrequency
13. 13The connections to a transformer are marked with Hs and Xs. A high voltage winding would be one marked:

    1. AX1 & X2
    2. B. X and H
    3. CH and X
    4. DH1 & H2
14. 14
    The peak to peak value of a voltage or current is _________ times the peak value.

    1. A1.414
    2. B2
    3. C1.73
    4. D0.707
15. 15If a transformer has 400 turns in the primary winding and 40 turns in the secondary winding and the secondary current is 10 A, the primary current will be _______________.

    1. A3.14A
    2. B1A
    3. C35A
    4. D10A

Descripción

Test sobre Class 2 Midterm part 2, creado por Regino Callan el 30/11/2020.

Autor

Regino Callan

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English

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