Ray Optics And Wave Optics

14 Questions
  1. 1
    Rainbow is produced when sunlight falls on drops of rain. Which of the following physical phenomena are responsible for this?
    1. Dispersion
    2. Refraction
    3. Internal reflection
    Select the correct answer using the codes given below.
    UPSC CSE I - 2013
  2. 2
    Consider the following phenomena:
    1. Size of the sun at dusk
    2. Colour of the sun at dawn
    3. Moon being visible at dawn
    4. Twinkle of stars in the sky
    5. Polestar being visible in the sky
    Which of the above are optical illusions?
    UPSC CSE I - 2013
  3. 3

    Consider the following statements:

    1. If magenta and yellow coloured circles intersect, the intersected area will have red colour.
    2. If cyan and magenta coloured circles intersect, the intersected area will have blue colour.

    Which of the statements given above is/are correct?

    UPSC CSE I - 2007
  4. 4

    Consider the following natural phenomena:

    1. Terrestrial heating
    2. Reflection of light
    3. Refraction of light
    4. Diffraction of light

    Due to which of these phenomena is a mirage formed?

    UPSC CSE I - 2002
  5. 5

    Assertion (A): A stick is dipped in water in a slanting position. If observed sideways, the stick appears short and bent at the surface of water.

    Reason (R): A light coming from the stick undergoes scattering from water molecules giving the stick a short and bent appearance.

    UPSC CSE I - 2001
  6. 6

    When a CD (compact disc used in audio and video systems) is seen in sunlight, rainbow like colours are seen. This can be explained on the basis of the phenomenon of:

    UPSC CSE I - 2001
  7. 7

    When light waves pass from air to glass, the variables affected are:

    UPSC CSE I - 2001
  8. 8

    Assertion (A): In a motion picture, usually 24 frames are projected every second over the whole length of the film. Reason (R): An image formed on the retina of eye persists for about 0.1 s after the removal of stimulus.

    UPSC CSE I - 2000
  9. 9

    Assertion (A): Small glass beads fixed on traffic signals glow brightly when light falls upon them. Reason (R): Light is totally reflected when the angle of incidence exceeds a certain critical value and light travelling in a denser medium is reflected from a rarer medium.

    UPSC CSE I - 2000
  10. 10

    When a CD (Compact Disc used in audio and video systems) is seen in sunlight, rainbow like colours is seen. This can be explained on the basis of the phenomenon of

    UPSC CSE I - 2000
  11. 11

    Consider the following statements:

    1. If a person looks at a coin which is in a bucket of water, the coin will appear to be closer than it really is.
    2. If a person under water looks at a coin above, the water surface, the coin will appear to be at a higher level than it really is.

    Which of the above statements is/are correct?

    UPSC CSE I - 1999
  12. 12

    Endoscopy, a technique used to explore the stomach or other inner parts of the body is based on the phenomenon of

    UPSC CSE I - 1999
  13. 13

    When a mirror is rotated by an angle θ, the reflected ray will rotate by:

    UPSC CSE I - 1996
  14. 14

    Total internal reflection can take place when light travels from:

    UPSC CSE I - 1996