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General Knowledge :: Physics

  1. If a carrier wave of 1000 kHz is used to carry the signal, the length of transmitting antenna will be equal to ________.

  2. A.

     300 m

    B.

     30 m

    C.

     3 m

    D.

     0.3 m


  3. Waves that are required for long distance wireless communication are

  4. A.

     Infrared rays

    B.

     Ultraviolet rays

    C.

     Radio waves

    D.

     Microwaves


  5. A television channel is characterised by

  6. A.

     Frequency of transmitted signal

    B.

     Velocity of transmitted signal

    C.

     Physical dimension of television screen

    D.

     Size of picture tube


  7. What is found in frequency modulation ?

  8. A.

     Fixed frequency

    B.

     Fixed dimension

    C.

     Change in frequency and dimension

    D.

     Change in dimension only


  9. Positive feedback is used in

  10. A.

     Amplifiers

    B.

     Rectifiers

    C.

     Oscillators

    D.

     None of these


  11. The waveform of a certain signal can be studied by

  12. A.

     Spectrometer

    B.

     Cathode ray oscilloscope

    C.

     P – n junction diode

    D.

     Sonometer


  13. The GPS device in an automobile uses which communication channel?

  14. A.

     Satellite

    B.

     Microwave

    C.

     Radio frequency

    D.

     Infrared


  15. In a optical fibre cable, the signal is propagated along the

  16. A.

     Inner Core

    B.

     Cladding

    C.

     Both core and cladding

    D.

     Surface and cladding


  17. The audio signals of TV are

  18. A.

     Amplitude modulated

    B.

     Frequency modulated

    C.

     Unmodulated

    D.

     Velocity modulated


  19. In radio-communication, the signals emitted by transmitting antenna are reflected on

  20. A.

     Stratosphere

    B.

     Ozonosphere

    C.

     Ionosphere

    D.

     Troposphere