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General Knowledge :: Physics

  1. Find the power of a convex lens if the image formed is at a distance of 25 cm from the lens when the object is placed on the other side of the lens at 12 cm from the optical centre?

  2. A.

     -4.33 diopters

    B.

     12.33 diopters

    C.

     -12.33 diopters

    D.

     4.33 diopters


  3. Find the power of a convex lens if the image formed is at a distance of 16 cm from the lens when the object is placed on the other side of the lens at 20 cm from the optical centre?

  4. A.

     -3.75 diopters

    B.

     -11.25 diopters

    C.

     3.75 diopters

    D.

     11.25 diopters


  5. A colour-blind person cannot

  6. A.

     See distant objects

    B.

     See black colour

    C.

     Distinguish between certain colours

    D.

     Have persistence of vision


  7. Magnifying Glass is basically a

  8. A.

     Plano-concave lens

    B.

     Concave lens

    C.

     Convex lens

    D.

     Cylindrical lens


  9. A microscope used in pathological laboratories forms

  10. A.

     Magnified, virtual, erect image

    B.

     Diminished, real and erect image

    C.

     Magnified, virtual and inverted image

    D.

     Diminished, virtual and erect image


  11. Which of the following characteristics of light remains unchanged when light travels from vaccum enters water?

  12. A.

     Speed

    B.

     Amplitude

    C.

     Frequency

    D.

     Wavelength


  13. To resolve an object in an electron microscope,

  14. A.

     The wavelength of the electrons must be close to the diameter of the object

    B.

     The wavelength of the electrons must be greater than the diameter of the object.

    C.

     Both A & B

    D.

     None of the above


  15. Which of the following is an example of continous emission spectrum?

  16. A.

     Spectrum of an oil frame

    B.

     Spectrum of a water

    C.

     Both

    D.

     None


  17. The atmospheric layer reflecting radio waves is called

  18. A.

     Ozonosphere

    B.

     Ionosphere

    C.

     Stratosphere

    D.

     Mesosphere


  19. For a ray of light to suffer total internal reflection it has to pass from :

  20. A.

     Glass to water

    B.

     Water to glass

    C.

     Air to water

    D.

     Air to glass