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General Knowledge :: Physics

  1. After removing two electrons from helium atom it become?

  2. A.

     UV rays

    B.

     Alpha particle

    C.

     Gama particle

    D.

     X rays


  3. Atomic packing factor of body centred cubic structure (bcc) is

  4. A.

     0.63

    B.

     0.68

    C.

     0.69

    D.

     0.73


  5. A nuclear reactor is said to have become 'critical' when

  6. A.

     It stops due to malfunctioning

    B.

     It starts emitting dangerous radioactive radiations

    C.

     It is shut down to avoid explosion

    D.

     It is ready to produce controlled energy


  7. Nuclear reactors used to produce electricity are based on

  8. A.

     Nuclear fission

    B.

     Nuclear fusion

    C.

     Cold fusion

    D.

     Superconductivity


  9. The energy obtained from atoms is known as ________

  10. A.

     Solar energy

    B.

     Heat energy

    C.

     Nuclear energy

    D.

     Chemical energy


  11. Which, of the following radiations has the least wavelength ?

  12. A.

     X-rays

    B.

     A-rays

    C.

     G-rays

    D.

     B-rays


  13. For Gamma radiation, what stops its penetrating abilities?

  14. A.

     Lead

    B.

     Steal

    C.

     Concrete

    D.

     All of the above


  15. An atom bomb based upon the principle of ________

  16. A.

     Nuclear fission

    B.

     Nuclear fussion

    C.

     Controlled chain reaction

    D.

     None of these


  17. The damage of the human body due to radiation (X-rays or gamma rays etc) is measured in :

  18. A.

     Rems

    B.

     Roentgen

    C.

     Curie

    D.

     Rads


  19. Radioactivity is due to

  20. A.

     Unstable nucleus

    B.

     Stable nucleus

    C.

     Stable electronic configuration

    D.

     Stable electronic configuration