How much do we need to know about Young's double slit and Interference/Difractio

[MCAT guy]

we didn't cover interference/difraction or similar topics very well in my physics course. How much depth do I need to go on this? I have a review sheet that includes this info:

Is this plenty?

Light (Electromagnetic Radiation)

• Concept of interference, Young double slit experiment
  • Review basic interference concepts here
  • In order for interference to occur, the follow conditions must hold:
    • the interfering light sources must be coherent. This means they must constantly maintain the same phase relationship. The light coming from the two slits in Young's double slit experiment are coherent because a single light source shines through both slits.
    • the light source must be monochromatic (of single color/wavelength).
  • 
    • dsinθ = mλ
    • bright bands occur at m = 0, +/-1, +/-2 ...etc
    • dark bands occur at m = +/-0.5, +/-1.5, +/-2.5 ...etc
• Thin films, diffraction grating, single slit diffraction
  • Thin films provide a means for interference to occur.
    • Light reflecting off the outer and inner boundary of a thin film interfere with each other.
    • A film of oil on water has the appearance of a swirly rainbow due to this interference.
  • 
  • Diffraction grating
    • Diffraction = light spreads out after passing through the slit, instead of going in a straight path.
    • Diffraction grating = a slab with many slits close together.
    • The equation for a diffraction grating is the same as the double-slit experiment.
    • dsinθ = mλ
    • d is the distance between the slits, everything else is the same as the double-slit experiment.
    • bright bands occur at m = 0, +/-1, +/-2 ...etc
    • dark bands occur at m = +/-0.5, +/-1.5, +/-2.5 ...etc
  • Single slit
    • Light shining through a single slit casts a central bright band followed by a series of maximas and minimas on either side.
    • The equation for a single slit diffraction is different from the equation for the double slit.
    • asinθ = mλ
    • a is the width of the slit.
    • Maxima occurs for m = 0 (big central maxima), +/-1.5, +/-2.5 , etc.
    • Minima occurs for m = +/-1, +/-2, +/-3, etc.
• Other diffraction phenomena, X-ray diffraction
  • Light shining through a pin hole will not appear on the screen as a pin hole. Instead, it will be a diffraction pattern of circular bright and dark bands, with a central bright band.
  • Light shining past an opaque boundary will not cast a sharp shadow of the boundary on the screen. Instead, fringes of bright and dark bands appear above the boundary.
  • Light shining past a penny will not cast a completely black shadow. Instead, there will be a central bright spot, as well as patterns of bright and dark rings.
  • X-ray diffraction = X-rays diffracting on a crystal. Patterns of interference that results from this is used to deduce the structure of the molecules in the crystal.

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[MCAT4life]

there was a double slit experiment passage on an old AAMC Full length test, they took out this passage when they condensed the test into CBT. however it didn't require you to really know all the details about the experiment, it was a tough passage, but it was really just an application of passage material. That being said, a passage like this showing up on the MCAT is pretty slim. The most light/optics problems that I see are ones that deal with Snell's law, lenses, but I would know the general concept of these experiments, such as the way that light diffracts, other than that I wouldn't bother memorizing the formula. MCAT goes around and asks college professors across the country what they cover the most in their class, they incorporate it into their tests that way, this is why you seldom see a lot tough electromagnetics//lenses//youngs since these topics are generally towards the end of the 2nd semester and a lot of profs don't concentrate on these... Mechanics on the other hand you need to know like the back of your hand.

 

[MCAT guy]

there was a double slit experiment passage on an old AAMC Full length test, they took out this passage when they condensed the test into CBT. however it didn't require you to really know all the details about the experiment, it was a tough passage, but it was really just an application of passage material. That being said, a passage like this showing up on the MCAT is pretty slim. The most light/optics problems that I see are ones that deal with Snell's law, lenses, but I would know the general concept of these experiments, such as the way that light diffracts, other than that I wouldn't bother memorizing the formula. MCAT goes around and asks college professors across the country what they cover the most in their class, they incorporate it into their tests that way, this is why you seldom see a lot tough electromagnetics//lenses//youngs since these topics are generally towards the end of the 2nd semester and a lot of profs don't concentrate on these... Mechanics on the other hand you need to know like the back of your hand.

Thanks bro.

 

[JP2740]

Can I assume if a topic isn't in the princeton books I can probably get it off of passage info?

 

[Rayhaan]

Can I assume if a topic isn't in the princeton books I can probably get it off of passage info?

No as I posted in your other thread. It is your choice to study it or not, but the topic lists are your source of the topics to study (not princeton). Though I doubt there would be an entire passage on this topic, probably like 1 question on the entire thing, and you said your exam is soon so it might not be worth the time to learn it all. I would recommend you just understand how the slit experiment works it shouldn't take that long.