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General Knowledge :: Physics

  1. Which of the following is a device designed to protect electrical devices from voltage spikes?

  2. A.

     Voltage unloader

    B.

     Surge protector

    C.

     Heat protector

    D.

     Current unloader


  3. The working of the quartz crystal in the watch is based on the

  4. A.

     Piezo - electric Effect

    B.

     Edison Effect

    C.

     Photoelectric Effect

    D.

     Johnson Effect


  5. At low temperature, Lead behaves as a :

  6. A.

     Semi conductor

    B.

     Superconductor

    C.

     Insulator

    D.

     Conductor


  7. The device which transfer the signal from low resistance region to high resistance region is

  8. A.

     Diode

    B.

     Transistor

    C.

     Capacitor

    D.

     Inductor


  9. The frequency of direct current is ________

  10. A.

     Zero

    B.

     50 HZ

    C.

     60 HZ

    D.

     100 HZ


  11. Resistance of human body in dry condition

  12. A.

     10 ohm

    B.

     1000 ohm

    C.

     10000 ohm

    D.

     100000 ohm


  13. The purpose of choke in a fluorescent lamp is :

  14. A.

     To increase the current flow

    B.

     To decrease the current flow

    C.

     To decrease the resistance

    D.

     Ro decrease the voltage momentarily


  15. An electron and a proton starting from rest get accelerated through potential difference of 100 kV. The final speed of the electron and the proton are Ve and Vp respectively. Which of the following relations is correct?

  16. A.

     Ve > Vp

    B.

     Ve < Vp

    C.

     Ve = Vp

    D.

     Cannot be determined


  17. Superconductors are those elements

  18. A.

     Whose conductivity is intermediate between metals and insulators

    B.

     Whose resistance falls almost to zero at very low temperatures

    C.

     Which turn into insulators at very low temperatures

    D.

     Which conduct electricity only at super-high temperatures


  19. A device used for converting a.c. into d.c. is called

  20. A.

     Transformer

    B.

     Rectifier

    C.

     Induction coil

    D.

     Dynamo