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Homework Help: Multiple Choice Questions ( NEED HELP )

  1. Mar 6, 2005 #1
    Multiple Choice Questions ( NEED HELP!! )

    Q. The bright and dark bands you see in a photograph of a double slit interference pattern represent which of the following?

    a. The respective positions of the crests and troughs of the light wave.
    b. An interference pattern that is not present unless it is produced by the camera lens.
    c. Locations of constructive / destructive intereference of light from the two sources.
    d. Constructive interference of light from the two sources.
    e. The presence of bright and dark particles of light.

    Q. When you look at a single slit diffraction pattern produced on a screen by light of a single wavelength, you see a bright central maximum and a number of maxima on either side, their intensity decreasing with distance from the central maximum. If the wavelength of the light is increased:

     The pattern shrinks in size. (central maximum less wide; other maxima in closer to it)
     The pattern increases in size. (central maximum wider; other maxima farther from it)
     It does not affect the size of the pattern.
     The width of the central maximum increases, but the other maxima do not change in position or width.
     The width of the central maximum decreases, but the other maxima do not change in position or width.

    4. Light of wavelength  passes through a single slit of width A and forms a diffraction pattern on a screen. If this light is replaced by another light of wavelength 3/2 , the original spacing of the diffraction pattern is reproduced if the slit width is changed to

     2A/3  3A/2  No change  4A/9  9A/4
    Q.What should the difference in the optical path lengths between two rays be to interfere

    (a) constructively and
    (b) destructively , Answer reqrd, both in terms of radians and in wavelengths.
  2. jcsd
  3. Mar 6, 2005 #2


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    Science Advisor

    For single-slit diffraction:
    {Angular Displacement of First Minimum} = θ =approx= λ/d

  4. Mar 6, 2005 #3
    can water wave be a longitudinal wave?
  5. Mar 6, 2005 #4


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    Science Advisor

    Beneath the surface (within the water volume itself), sound travels in water with a longitudinal wave.

    Last edited: Mar 6, 2005
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